diff --git a/src/core/adaptive/adaptive_representation_selector.ts b/src/core/adaptive/adaptive_representation_selector.ts
index 93493248c9..25856f706b 100644
--- a/src/core/adaptive/adaptive_representation_selector.ts
+++ b/src/core/adaptive/adaptive_representation_selector.ts
@@ -24,8 +24,8 @@ import type {
   ISegment,
 } from "../../manifest";
 import type {
-  ObservationPosition,
   IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
 } from "../../playback_observer";
 import isNullOrUndefined from "../../utils/is_null_or_undefined";
 import noop from "../../utils/noop";
@@ -96,7 +96,7 @@ export default function createAdaptiveRepresentationSelector(
     context: { manifest: IManifest; period: IPeriod; adaptation: IAdaptation },
     currentRepresentation: IReadOnlySharedReference<IRepresentation | null>,
     representations: IReadOnlySharedReference<IRepresentation[]>,
-    playbackObserver: IReadOnlyPlaybackObserver<IRepresentationEstimatorPlaybackObservation>,
+    playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>,
     stopAllEstimates: CancellationSignal,
   ): IRepresentationEstimatorResponse {
     const { type } = context.adaptation;
@@ -636,29 +636,6 @@ export interface IABREstimate {
   knownStableBitrate?: number | undefined;
 }
 
-/** Media properties `getEstimateReference` will need to keep track of. */
-export interface IRepresentationEstimatorPlaybackObservation {
-  /**
-   * For the concerned media buffer, difference in seconds between the next
-   * position where no segment data is available and the current position.
-   */
-  bufferGap: number;
-  /**
-   * Information on the current media position in seconds at the time of a
-   * Playback Observation.
-   */
-  position: ObservationPosition;
-  /**
-   * Last "playback rate" set by the user. This is the ideal "playback rate" at
-   * which the media should play.
-   */
-  speed: number;
-  /** `duration` property of the HTMLMediaElement on which the content plays. */
-  duration: number;
-  /** Theoretical maximum position on the content that can currently be played. */
-  maximumPosition: number;
-}
-
 /** Content of the `IABRMetricsEvent` event's payload. */
 export interface IMetricsCallbackPayload {
   /** Time the request took to perform the request, in milliseconds. */
@@ -747,7 +724,7 @@ export interface IRepresentationEstimatorArguments {
   /** Class allowing to estimate the current network bandwidth. */
   bandwidthEstimator: BandwidthEstimator;
   /** Emit regular playback information. */
-  playbackObserver: IReadOnlyPlaybackObserver<IRepresentationEstimatorPlaybackObservation>;
+  playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>;
   /**
    * The Representation currently loaded.
    * `null` if no Representation is currently loaded.
@@ -797,7 +774,7 @@ export type IRepresentationEstimator = (
   /** Reference emitting the list of available Representations to choose from. */
   representations: IReadOnlySharedReference<IRepresentation[]>,
   /** Regularly emits playback conditions */
-  playbackObserver: IReadOnlyPlaybackObserver<IRepresentationEstimatorPlaybackObservation>,
+  playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>,
   /**
    * After this `CancellationSignal` emits, resources will be disposed and
    * estimates will stop to be emitted.
diff --git a/src/core/adaptive/index.ts b/src/core/adaptive/index.ts
index 7fe3e0bdfb..1353e00db6 100644
--- a/src/core/adaptive/index.ts
+++ b/src/core/adaptive/index.ts
@@ -21,7 +21,6 @@ import type {
   IMetricsCallbackPayload,
   IRepresentationEstimator,
   IRepresentationEstimatorCallbacks,
-  IRepresentationEstimatorPlaybackObservation,
   IRepresentationEstimatorThrottlers as IABRThrottlers,
   IRequestBeginCallbackPayload,
   IRequestEndCallbackPayload,
@@ -39,7 +38,6 @@ export type {
   IABREstimate,
   IMetricsCallbackPayload,
   IRepresentationEstimatorCallbacks,
-  IRepresentationEstimatorPlaybackObservation,
   IRequestBeginCallbackPayload,
   IRequestProgressCallbackPayload,
   IRequestEndCallbackPayload,
diff --git a/src/core/adaptive/network_analyzer.ts b/src/core/adaptive/network_analyzer.ts
index 5941ae12f7..125357c84b 100644
--- a/src/core/adaptive/network_analyzer.ts
+++ b/src/core/adaptive/network_analyzer.ts
@@ -17,10 +17,10 @@
 import config from "../../config";
 import log from "../../log";
 import type { IRepresentation } from "../../manifest";
+import type { IAdaptationStreamPlaybackObservation } from "../../playback_observer";
 import arrayFind from "../../utils/array_find";
 import isNullOrUndefined from "../../utils/is_null_or_undefined";
 import getMonotonicTimeStamp from "../../utils/monotonic_timestamp";
-import type { IRepresentationEstimatorPlaybackObservation } from "./adaptive_representation_selector";
 import type BandwidthEstimator from "./utils/bandwidth_estimator";
 import EWMA from "./utils/ewma";
 import type {
@@ -30,7 +30,7 @@ import type {
 
 /** Object describing the current playback conditions. */
 type IPlaybackConditionsInfo = Pick<
-  IRepresentationEstimatorPlaybackObservation,
+  IAdaptationStreamPlaybackObservation,
   "bufferGap" | "position" | "speed" | "duration"
 >;
 
diff --git a/src/core/cmcd/cmcd_data_builder.ts b/src/core/cmcd/cmcd_data_builder.ts
index ffad5efcc5..1ca45a5b0d 100644
--- a/src/core/cmcd/cmcd_data_builder.ts
+++ b/src/core/cmcd/cmcd_data_builder.ts
@@ -8,13 +8,11 @@ import type {
 } from "../../manifest";
 import type {
   IReadOnlyPlaybackObserver,
-  IRebufferingStatus,
-  ObservationPosition,
+  ICorePlaybackObservation,
 } from "../../playback_observer";
 import type { ICmcdOptions, ICmcdPayload, ITrackType } from "../../public_types";
 import createUuid from "../../utils/create_uuid";
 import isNullOrUndefined from "../../utils/is_null_or_undefined";
-import type { IRange } from "../../utils/ranges";
 import TaskCanceller from "../../utils/task_canceller";
 import { getRelativeUrl } from "../../utils/url-utils";
 
@@ -59,34 +57,6 @@ export interface ICmcdSegmentInfo {
   nextSegment: ISegment | null | undefined;
 }
 
-/**
- * Media playback observation's properties the `CmcdDataBuilder` wants to have
- * access to.
- */
-export interface ICmcdDataBuilderPlaybackObservation {
-  /**
-   * Ranges of buffered data per type of media.
-   * `null` if no buffer exists for that type of media.
-   */
-  buffered: Record<ITrackType, IRange[] | null>;
-  /**
-   * Information on the current media position in seconds at the time of the
-   * Observation.
-   */
-  position: ObservationPosition;
-  /** Target playback rate at which we want to play the content. */
-  speed: number;
-  /**
-   * Describes when the player is "rebuffering" and what event started that
-   * status.
-   * "Rebuffering" is a status where the player has not enough buffer ahead to
-   * play reliably.
-   * The RxPlayer should pause playback when a playback observation indicates the
-   * rebuffering status.
-   */
-  rebuffering: IRebufferingStatus | null;
-}
-
 /**
  * Class allowing to easily obtain "Common Media Client Data" (CMCD) properties
  * that may be relied on while performing HTTP(S) requests on a CDN.
@@ -98,7 +68,7 @@ export default class CmcdDataBuilder {
   private _contentId: string;
   private _typePreference: TypePreference;
   private _lastThroughput: Partial<Record<ITrackType, number | undefined>>;
-  private _playbackObserver: IReadOnlyPlaybackObserver<ICmcdDataBuilderPlaybackObservation> | null;
+  private _playbackObserver: IReadOnlyPlaybackObserver<ICorePlaybackObservation> | null;
   private _bufferStarvationToggle: boolean;
   private _canceller: TaskCanceller | null;
 
@@ -131,7 +101,7 @@ export default class CmcdDataBuilder {
    * @param {Object} playbackObserver
    */
   public startMonitoringPlayback(
-    playbackObserver: IReadOnlyPlaybackObserver<ICmcdDataBuilderPlaybackObservation>,
+    playbackObserver: IReadOnlyPlaybackObserver<ICorePlaybackObservation>,
   ): void {
     this._canceller?.cancel();
     this._canceller = new TaskCanceller();
diff --git a/src/core/cmcd/index.ts b/src/core/cmcd/index.ts
index fc4f770e64..d8146c54ca 100644
--- a/src/core/cmcd/index.ts
+++ b/src/core/cmcd/index.ts
@@ -1,7 +1,4 @@
 import CmcdDataBuilder from "./cmcd_data_builder";
 
-export type {
-  ICmcdSegmentInfo,
-  ICmcdDataBuilderPlaybackObservation,
-} from "./cmcd_data_builder";
+export type { ICmcdSegmentInfo } from "./cmcd_data_builder";
 export default CmcdDataBuilder;
diff --git a/src/core/main/worker/worker_main.ts b/src/core/main/worker/worker_main.ts
index 523d778fba..86466703b9 100644
--- a/src/core/main/worker/worker_main.ts
+++ b/src/core/main/worker/worker_main.ts
@@ -13,7 +13,7 @@ import { MainThreadMessageType, WorkerMessageType } from "../../../multithread_t
 import DashFastJsParser from "../../../parsers/manifest/dash/fast-js-parser";
 import DashWasmParser from "../../../parsers/manifest/dash/wasm-parser";
 import { ObservationPosition } from "../../../playback_observer";
-import type { IWorkerPlaybackObservation } from "../../../playback_observer/worker_playback_observer";
+import type { ICorePlaybackObservation } from "../../../playback_observer/types";
 import WorkerPlaybackObserver from "../../../playback_observer/worker_playback_observer";
 import type { IPlayerError, ITrackType } from "../../../public_types";
 import createDashPipelines from "../../../transports/dash";
@@ -79,7 +79,7 @@ export default function initializeWorkerMain() {
   /**
    * When set, emit playback observation made on the main thread.
    */
-  let playbackObservationRef: SharedReference<IWorkerPlaybackObservation> | null = null;
+  let playbackObservationRef: SharedReference<ICorePlaybackObservation> | null = null;
 
   globalScope.onmessageerror = (_msg: MessageEvent) => {
     log.error("MTCI: Error when receiving message from main thread.");
@@ -140,7 +140,7 @@ export default function initializeWorkerMain() {
 
         const currentCanceller = new TaskCanceller();
         const currentContentObservationRef =
-          new SharedReference<IWorkerPlaybackObservation>(
+          new SharedReference<ICorePlaybackObservation>(
             objectAssign(msg.value.initialObservation, {
               position: new ObservationPosition(...msg.value.initialObservation.position),
             }),
@@ -484,7 +484,7 @@ interface IBufferingInitializationInformation {
 function loadOrReloadPreparedContent(
   val: IBufferingInitializationInformation,
   contentPreparer: ContentPreparer,
-  playbackObservationRef: IReadOnlySharedReference<IWorkerPlaybackObservation>,
+  playbackObservationRef: IReadOnlySharedReference<ICorePlaybackObservation>,
   parentCancelSignal: CancellationSignal,
 ) {
   const currentLoadCanceller = new TaskCanceller();
diff --git a/src/core/stream/adaptation/get_representations_switch_strategy.ts b/src/core/stream/adaptation/get_representations_switch_strategy.ts
index f57fdf9069..4337b462a6 100644
--- a/src/core/stream/adaptation/get_representations_switch_strategy.ts
+++ b/src/core/stream/adaptation/get_representations_switch_strategy.ts
@@ -16,7 +16,10 @@
 
 import config from "../../../config";
 import type { IAdaptation, IPeriod } from "../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../playback_observer";
+import type {
+  IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
+} from "../../../playback_observer";
 import arrayIncludes from "../../../utils/array_includes";
 import type { IRange } from "../../../utils/ranges";
 import { excludeFromRanges, insertInto } from "../../../utils/ranges";
@@ -26,17 +29,14 @@ import {
   getLastSegmentBeforePeriod,
   SegmentSinkOperation,
 } from "../../segment_sinks";
-import type {
-  IRepresentationsChoice,
-  IRepresentationStreamPlaybackObservation,
-} from "../representation";
+import type { IRepresentationsChoice } from "../representation";
 
 export default function getRepresentationsSwitchingStrategy(
   period: IPeriod,
   adaptation: IAdaptation,
   settings: IRepresentationsChoice,
   segmentSink: SegmentSink,
-  playbackObserver: IReadOnlyPlaybackObserver<IRepresentationStreamPlaybackObservation>,
+  playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>,
 ): IRepresentationSwitchStrategy {
   if (settings.switchingMode === "lazy") {
     return { type: "continue", value: undefined };
diff --git a/src/core/stream/adaptation/types.ts b/src/core/stream/adaptation/types.ts
index 862466a416..5a36efc3ca 100644
--- a/src/core/stream/adaptation/types.ts
+++ b/src/core/stream/adaptation/types.ts
@@ -1,5 +1,8 @@
 import type { IManifest, IAdaptation, IPeriod, IRepresentation } from "../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../playback_observer";
+import type {
+  IAdaptationStreamPlaybackObservation,
+  IReadOnlyPlaybackObserver,
+} from "../../../playback_observer";
 import type {
   IAudioTrackSwitchingMode,
   IVideoTrackSwitchingMode,
@@ -11,7 +14,6 @@ import type { IBufferType, SegmentSink } from "../../segment_sinks";
 import type {
   IRepresentationsChoice,
   IRepresentationStreamCallbacks,
-  IRepresentationStreamPlaybackObservation,
 } from "../representation";
 
 /** Callbacks called by the `AdaptationStream` on various events. */
@@ -110,20 +112,6 @@ export interface INeedsBufferFlushPayload {
   relativePosHasBeenDefaulted: boolean;
 }
 
-/** Regular playback information needed by the AdaptationStream. */
-export interface IAdaptationStreamPlaybackObservation
-  extends IRepresentationStreamPlaybackObservation {
-  /**
-   * For the current SegmentSink, difference in seconds between the next position
-   * where no segment data is available and the current position.
-   */
-  bufferGap: number;
-  /** `duration` property of the HTMLMediaElement on which the content plays. */
-  duration: number;
-  /** Theoretical maximum position on the content that can currently be played. */
-  maximumPosition: number;
-}
-
 /** Arguments given when creating a new `AdaptationStream`. */
 export interface IAdaptationStreamArguments {
   /** Regularly emit playback conditions. */
diff --git a/src/core/stream/period/period_stream.ts b/src/core/stream/period/period_stream.ts
index 531c1813ec..71ae18363c 100644
--- a/src/core/stream/period/period_stream.ts
+++ b/src/core/stream/period/period_stream.ts
@@ -19,7 +19,10 @@ import { formatError, MediaError } from "../../../errors";
 import log from "../../../log";
 import type { IAdaptation, IPeriod } from "../../../manifest";
 import { toTaggedTrack } from "../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../playback_observer";
+import type {
+  IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
+} from "../../../playback_observer";
 import type { ITrackType } from "../../../public_types";
 import arrayFind from "../../../utils/array_find";
 import objectAssign from "../../../utils/object_assign";
@@ -31,11 +34,7 @@ import type { CancellationSignal } from "../../../utils/task_canceller";
 import TaskCanceller, { CancellationError } from "../../../utils/task_canceller";
 import type { IBufferType, SegmentSink } from "../../segment_sinks";
 import SegmentSinksStore from "../../segment_sinks";
-import type {
-  IAdaptationChoice,
-  IAdaptationStreamCallbacks,
-  IAdaptationStreamPlaybackObservation,
-} from "../adaptation";
+import type { IAdaptationChoice, IAdaptationStreamCallbacks } from "../adaptation";
 import AdaptationStream from "../adaptation";
 import type { IRepresentationsChoice } from "../representation";
 import type {
diff --git a/src/core/stream/representation/types.ts b/src/core/stream/representation/types.ts
index 4c37c5cbfc..ea88dbef2e 100644
--- a/src/core/stream/representation/types.ts
+++ b/src/core/stream/representation/types.ts
@@ -8,8 +8,8 @@ import type {
 } from "../../../manifest";
 import type { IEMSG } from "../../../parsers/containers/isobmff";
 import type {
-  ObservationPosition,
   IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
 } from "../../../playback_observer";
 import type {
   IAudioRepresentationsSwitchingMode,
@@ -178,22 +178,6 @@ export interface IBufferDiscontinuity {
   end: number | null;
 }
 
-/** Object that should be emitted by the given `IReadOnlyPlaybackObserver`. */
-export interface IRepresentationStreamPlaybackObservation {
-  /**
-   * Information on the current media position in seconds at the time of a
-   * Playback Observation.
-   */
-  position: ObservationPosition;
-  /**
-   * Information on whether the media element was paused at the time of the
-   * Observation.
-   */
-  paused: IPausedPlaybackObservation;
-  /** Last "playback rate" asked by the user. */
-  speed: number;
-}
-
 /** Pause-related information linked to an emitted Playback observation. */
 export interface IPausedPlaybackObservation {
   /**
@@ -269,7 +253,7 @@ export interface IRepresentationStreamArguments<TSegmentDataType> {
    */
   terminate: IReadOnlySharedReference<null | ITerminationOrder>;
   /** Periodically emits the current playback conditions. */
-  playbackObserver: IReadOnlyPlaybackObserver<IRepresentationStreamPlaybackObservation>;
+  playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>;
   /** Supplementary arguments which configure the RepresentationStream's behavior. */
   options: IRepresentationStreamOptions;
 }
diff --git a/src/core/stream/representation/utils/append_segment_to_buffer.ts b/src/core/stream/representation/utils/append_segment_to_buffer.ts
index d7d57fb621..c1ed41a605 100644
--- a/src/core/stream/representation/utils/append_segment_to_buffer.ts
+++ b/src/core/stream/representation/utils/append_segment_to_buffer.ts
@@ -21,7 +21,10 @@
 import { MediaError, SourceBufferError } from "../../../../errors";
 import log from "../../../../log";
 import { toTaggedTrack } from "../../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../../playback_observer";
+import type {
+  IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
+} from "../../../../playback_observer";
 import type { IRange } from "../../../../utils/ranges";
 import type { IReadOnlySharedReference } from "../../../../utils/reference";
 import sleep from "../../../../utils/sleep";
@@ -32,7 +35,6 @@ import type {
   IPushChunkInfos,
   SegmentSink,
 } from "../../../segment_sinks";
-import type { IRepresentationStreamPlaybackObservation } from "../types";
 
 /**
  * Append a segment to the given segmentSink.
@@ -46,7 +48,7 @@ import type { IRepresentationStreamPlaybackObservation } from "../types";
  * @returns {Promise}
  */
 export default async function appendSegmentToBuffer<T>(
-  playbackObserver: IReadOnlyPlaybackObserver<IRepresentationStreamPlaybackObservation>,
+  playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>,
   segmentSink: SegmentSink,
   dataInfos: IPushChunkInfos<T> & { inventoryInfos: IInsertedChunkInfos },
   bufferGoal: IReadOnlySharedReference<number>,
diff --git a/src/core/stream/representation/utils/get_buffer_status.ts b/src/core/stream/representation/utils/get_buffer_status.ts
index 419324cab1..2d3bce886f 100644
--- a/src/core/stream/representation/utils/get_buffer_status.ts
+++ b/src/core/stream/representation/utils/get_buffer_status.ts
@@ -20,18 +20,17 @@ import type {
   IPeriod,
   IRepresentation,
 } from "../../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../../playback_observer";
+import type {
+  IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
+} from "../../../../playback_observer";
 import isNullOrUndefined from "../../../../utils/is_null_or_undefined";
 import type {
   ISignalCompleteSegmentOperation,
   SegmentSink,
 } from "../../../segment_sinks";
 import SegmentSinksStore, { SegmentSinkOperation } from "../../../segment_sinks";
-import type {
-  IBufferDiscontinuity,
-  IRepresentationStreamPlaybackObservation,
-  IQueuedSegment,
-} from "../types";
+import type { IBufferDiscontinuity, IQueuedSegment } from "../types";
 import checkForDiscontinuity from "./check_for_discontinuity";
 import getNeededSegments from "./get_needed_segments";
 import getSegmentPriority from "./get_segment_priority";
@@ -92,7 +91,7 @@ export default function getBufferStatus(
     representation: IRepresentation;
   },
   initialWantedTime: number,
-  playbackObserver: IReadOnlyPlaybackObserver<IRepresentationStreamPlaybackObservation>,
+  playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>,
   fastSwitchThreshold: number | undefined,
   bufferGoal: number,
   maxBufferSize: number,
diff --git a/src/core/stream/representation/utils/push_init_segment.ts b/src/core/stream/representation/utils/push_init_segment.ts
index e051310e56..1f89ff6fa8 100644
--- a/src/core/stream/representation/utils/push_init_segment.ts
+++ b/src/core/stream/representation/utils/push_init_segment.ts
@@ -21,15 +21,15 @@ import type {
   IPeriod,
   IRepresentation,
 } from "../../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../../playback_observer";
+import type {
+  IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
+} from "../../../../playback_observer";
 import objectAssign from "../../../../utils/object_assign";
 import type { IReadOnlySharedReference } from "../../../../utils/reference";
 import type { CancellationSignal } from "../../../../utils/task_canceller";
 import type { IPushedChunkData, SegmentSink } from "../../../segment_sinks";
-import type {
-  IRepresentationStreamPlaybackObservation,
-  IStreamEventAddedSegmentPayload,
-} from "../types";
+import type { IStreamEventAddedSegmentPayload } from "../types";
 import appendSegmentToBuffer from "./append_segment_to_buffer";
 
 /**
@@ -47,7 +47,7 @@ export default async function pushInitSegment<T>(
     segmentSink,
     bufferGoal,
   }: {
-    playbackObserver: IReadOnlyPlaybackObserver<IRepresentationStreamPlaybackObservation>;
+    playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>;
     content: {
       adaptation: IAdaptation;
       manifest: IManifest;
diff --git a/src/core/stream/representation/utils/push_media_segment.ts b/src/core/stream/representation/utils/push_media_segment.ts
index 65eff2a237..b4f34e65d3 100644
--- a/src/core/stream/representation/utils/push_media_segment.ts
+++ b/src/core/stream/representation/utils/push_media_segment.ts
@@ -22,16 +22,16 @@ import type {
   IPeriod,
   IRepresentation,
 } from "../../../../manifest";
-import type { IReadOnlyPlaybackObserver } from "../../../../playback_observer";
+import type {
+  IReadOnlyPlaybackObserver,
+  IAdaptationStreamPlaybackObservation,
+} from "../../../../playback_observer";
 import type { ISegmentParserParsedMediaChunk } from "../../../../transports";
 import objectAssign from "../../../../utils/object_assign";
 import type { IReadOnlySharedReference } from "../../../../utils/reference";
 import type { CancellationSignal } from "../../../../utils/task_canceller";
 import type { SegmentSink } from "../../../segment_sinks";
-import type {
-  IRepresentationStreamPlaybackObservation,
-  IStreamEventAddedSegmentPayload,
-} from "../types";
+import type { IStreamEventAddedSegmentPayload } from "../types";
 import appendSegmentToBuffer from "./append_segment_to_buffer";
 
 /**
@@ -50,7 +50,7 @@ export default async function pushMediaSegment<T>(
     segment,
     segmentSink,
   }: {
-    playbackObserver: IReadOnlyPlaybackObserver<IRepresentationStreamPlaybackObservation>;
+    playbackObserver: IReadOnlyPlaybackObserver<IAdaptationStreamPlaybackObservation>;
     content: {
       adaptation: IAdaptation;
       manifest: IManifest;
diff --git a/src/main_thread/init/multi_thread_content_initializer.ts b/src/main_thread/init/multi_thread_content_initializer.ts
index 107fa1cb14..53374fd49c 100644
--- a/src/main_thread/init/multi_thread_content_initializer.ts
+++ b/src/main_thread/init/multi_thread_content_initializer.ts
@@ -32,8 +32,8 @@ import { MainThreadMessageType, WorkerMessageType } from "../../multithread_type
 import type {
   IReadOnlyPlaybackObserver,
   IMediaElementPlaybackObserver,
+  ICorePlaybackObservation,
 } from "../../playback_observer";
-import type { IWorkerPlaybackObservation } from "../../playback_observer/worker_playback_observer";
 import type {
   ICmcdOptions,
   IInitialManifest,
@@ -1472,7 +1472,7 @@ export default class MultiThreadContentInitializer extends ContentInitializer {
       playbackObserver: IMediaElementPlaybackObserver;
     },
     cancelSignal: CancellationSignal,
-  ): IReadOnlyPlaybackObserver<IWorkerPlaybackObservation> | null {
+  ): IReadOnlyPlaybackObserver<ICorePlaybackObservation> | null {
     if (cancelSignal.isCancelled()) {
       return null;
     }
diff --git a/src/main_thread/init/utils/create_core_playback_observer.ts b/src/main_thread/init/utils/create_core_playback_observer.ts
index 1d18caf1a4..5109754a62 100644
--- a/src/main_thread/init/utils/create_core_playback_observer.ts
+++ b/src/main_thread/init/utils/create_core_playback_observer.ts
@@ -15,7 +15,6 @@
  */
 
 import getBufferedDataPerMediaBuffer from "../../../core/main/common/get_buffered_data_per_media_buffer";
-import type { IPausedPlaybackObservation } from "../../../core/types";
 import type { IManifestMetadata } from "../../../manifest";
 import { getMaximumSafePosition } from "../../../manifest";
 import type { IMediaSourceInterface } from "../../../mse";
@@ -23,12 +22,8 @@ import type {
   IPlaybackObservation,
   IReadOnlyPlaybackObserver,
   IMediaElementPlaybackObserver,
-  ObservationPosition,
-  IRebufferingStatus,
-  IFreezingStatus,
 } from "../../../playback_observer";
-import type { ITrackType } from "../../../public_types";
-import type { IRange } from "../../../utils/ranges";
+import type { ICorePlaybackObservation } from "../../../playback_observer/types";
 import type { IReadOnlySharedReference } from "../../../utils/reference";
 import SharedReference from "../../../utils/reference";
 import type { CancellationSignal } from "../../../utils/task_canceller";
@@ -55,35 +50,6 @@ export interface ICorePlaybackObserverArguments {
   mediaSource: IMediaSourceInterface | null;
 }
 
-export interface ICorePlaybackObservation {
-  /**
-   * Information on whether the media element was paused at the time of the
-   * Observation.
-   */
-  paused: IPausedPlaybackObservation;
-  /**
-   * Information on the current media position in seconds at the time of the
-   * Observation.
-   */
-  position: ObservationPosition;
-  /** `duration` property of the HTMLMediaElement. */
-  duration: number;
-  /** `readyState` property of the HTMLMediaElement. */
-  readyState: number;
-  /** Target playback rate at which we want to play the content. */
-  speed: number;
-  /** Theoretical maximum position on the content that can currently be played. */
-  maximumPosition: number;
-  /**
-   * Ranges of buffered data per type of media.
-   * `null` if no buffer exists for that type of media.
-   */
-  buffered: Record<ITrackType, IRange[] | null>;
-  rebuffering: IRebufferingStatus | null;
-  freezing: IFreezingStatus | null;
-  bufferGap: number | undefined;
-}
-
 /**
  * Create PlaybackObserver for the core part of the code.
  * @param {Object} srcPlaybackObserver - Base `PlaybackObserver` from which we
diff --git a/src/playback_observer/index.ts b/src/playback_observer/index.ts
index 8cedce3253..d8ffaef1ca 100644
--- a/src/playback_observer/index.ts
+++ b/src/playback_observer/index.ts
@@ -7,6 +7,9 @@ export type {
   IRebufferingStatus,
   IPlaybackObservation,
   IReadOnlyPlaybackObserver,
+  ICorePlaybackObservation,
+  IPeriodStreamPlaybackObservation,
+  IAdaptationStreamPlaybackObservation,
 } from "./types";
 export type IMediaElementPlaybackObserver = MediaElementPlaybackObserver;
 export { ObservationPosition };
diff --git a/src/playback_observer/types.ts b/src/playback_observer/types.ts
index 554c93b1cb..61cda0e2e8 100644
--- a/src/playback_observer/types.ts
+++ b/src/playback_observer/types.ts
@@ -1,3 +1,5 @@
+import type { ITrackType } from "../public_types";
+import type { IRange } from "../utils/ranges";
 import type { IReadOnlySharedReference } from "../utils/reference";
 import type { CancellationSignal } from "../utils/task_canceller";
 import type ObservationPosition from "./utils/observation_position";
@@ -236,3 +238,87 @@ export interface IReadOnlyPlaybackObserver<TObservationType> {
     ) => IReadOnlySharedReference<TDest>,
   ): IReadOnlyPlaybackObserver<TDest>;
 }
+
+export interface ICorePlaybackObservation extends IPeriodStreamPlaybackObservation {
+  rebuffering: IRebufferingStatus | null;
+  freezing: IFreezingStatus | null;
+  bufferGap: number | undefined;
+}
+
+/** Regular playback information needed by the AdaptationStream. */
+export interface IAdaptationStreamPlaybackObservation {
+  /**
+   * Information on whether the media element was paused at the time of the
+   * Observation.
+   */
+  paused: IPausedPlaybackObservation;
+  /**
+   * Information on the current media position in seconds at the time of the
+   * Observation.
+   */
+  position: ObservationPosition;
+  /** `duration` property of the HTMLMediaElement. */
+  duration: number;
+  /** `readyState` property of the HTMLMediaElement. */
+  readyState: number;
+  /** Target playback rate at which we want to play the content. */
+  speed: number;
+  /** Theoretical maximum position on the content that can currently be played. */
+  maximumPosition: number;
+  /**
+   * For the current SegmentSink, difference in seconds between the next position
+   * where no segment data is available and the current position.
+   */
+  bufferGap: number;
+  /**
+   * Ranges of buffered data for the adaptation media type.
+   * `null` if no buffer exists for the media type.
+   */
+  buffered: IRange[] | null;
+}
+
+export interface IPeriodStreamPlaybackObservation {
+  /**
+   * Information on whether the media element was paused at the time of the
+   * Observation.
+   */
+  paused: IPausedPlaybackObservation;
+  /**
+   * Information on the current media position in seconds at the time of the
+   * Observation.
+   */
+  position: ObservationPosition;
+  /** `duration` property of the HTMLMediaElement. */
+  duration: number;
+  /** `readyState` property of the HTMLMediaElement. */
+  readyState: number;
+  /** Target playback rate at which we want to play the content. */
+  speed: number;
+  /** Theoretical maximum position on the content that can currently be played. */
+  maximumPosition: number;
+  /**
+   * Ranges of buffered data per type of media.
+   * `null` if no buffer exists for that type of media.
+   */
+  buffered: Record<ITrackType, IRange[] | null>;
+}
+
+/** Pause-related information linked to an emitted Playback observation. */
+export interface IPausedPlaybackObservation {
+  /**
+   * Known paused state at the time the Observation was emitted.
+   *
+   * `true` indicating that the HTMLMediaElement was in a paused state.
+   *
+   * Note that it might have changed since. If you want truly precize
+   * information, you should recuperate it from the HTMLMediaElement directly
+   * through another mean.
+   */
+  last: boolean;
+  /**
+   * Actually wanted paused state not yet reached.
+   * This might for example be set to `false` when the content is currently
+   * loading (and thus paused) but with autoPlay enabled.
+   */
+  pending: boolean | undefined;
+}
diff --git a/src/playback_observer/worker_playback_observer.ts b/src/playback_observer/worker_playback_observer.ts
index 6244d2eabf..61e722fdb9 100644
--- a/src/playback_observer/worker_playback_observer.ts
+++ b/src/playback_observer/worker_playback_observer.ts
@@ -1,76 +1,20 @@
 import type { IUpdatePlaybackRateWorkerMessage } from "../multithread_types";
 import { WorkerMessageType } from "../multithread_types";
-import type { ITrackType } from "../public_types";
-import type { IRange } from "../utils/ranges";
 import type { IReadOnlySharedReference } from "../utils/reference";
 import type { CancellationSignal } from "../utils/task_canceller";
-import type {
-  IFreezingStatus,
-  IReadOnlyPlaybackObserver,
-  IRebufferingStatus,
-} from "./types";
+import type { ICorePlaybackObservation, IReadOnlyPlaybackObserver } from "./types";
 import generateReadOnlyObserver from "./utils/generate_read_only_observer";
-import type ObservationPosition from "./utils/observation_position";
-
-export interface IWorkerPlaybackObservation {
-  /**
-   * Information on whether the media element was paused at the time of the
-   * Observation.
-   */
-  paused: IPausedPlaybackObservation;
-  /**
-   * Information on the current media position in seconds at the time of the
-   * Observation.
-   */
-  position: ObservationPosition;
-  /** `duration` property of the HTMLMediaElement. */
-  duration: number;
-  /** `readyState` property of the HTMLMediaElement. */
-  readyState: number;
-  /** Target playback rate at which we want to play the content. */
-  speed: number;
-  /** Theoretical maximum position on the content that can currently be played. */
-  maximumPosition: number;
-  /**
-   * Ranges of buffered data per type of media.
-   * `null` if no buffer exists for that type of media.
-   */
-  buffered: Record<ITrackType, IRange[] | null>;
-  rebuffering: IRebufferingStatus | null;
-  freezing: IFreezingStatus | null;
-  bufferGap: number | undefined;
-}
-
-/** Pause-related information linked to an emitted Playback observation. */
-export interface IPausedPlaybackObservation {
-  /**
-   * Known paused state at the time the Observation was emitted.
-   *
-   * `true` indicating that the HTMLMediaElement was in a paused state.
-   *
-   * Note that it might have changed since. If you want truly precize
-   * information, you should recuperate it from the HTMLMediaElement directly
-   * through another mean.
-   */
-  last: boolean;
-  /**
-   * Actually wanted paused state not yet reached.
-   * This might for example be set to `false` when the content is currently
-   * loading (and thus paused) but with autoPlay enabled.
-   */
-  pending: boolean | undefined;
-}
 
 export default class WorkerPlaybackObserver
-  implements IReadOnlyPlaybackObserver<IWorkerPlaybackObservation>
+  implements IReadOnlyPlaybackObserver<ICorePlaybackObservation>
 {
-  private _src: IReadOnlySharedReference<IWorkerPlaybackObservation>;
+  private _src: IReadOnlySharedReference<ICorePlaybackObservation>;
   private _cancelSignal: CancellationSignal;
   private _messageSender: (msg: IUpdatePlaybackRateWorkerMessage) => void;
   private _contentId: string;
 
   constructor(
-    src: IReadOnlySharedReference<IWorkerPlaybackObservation>,
+    src: IReadOnlySharedReference<ICorePlaybackObservation>,
     contentId: string,
     sendMessage: (msg: IUpdatePlaybackRateWorkerMessage) => void,
     cancellationSignal: CancellationSignal,
@@ -93,7 +37,7 @@ export default class WorkerPlaybackObserver
     return undefined;
   }
 
-  public getReference(): IReadOnlySharedReference<IWorkerPlaybackObservation> {
+  public getReference(): IReadOnlySharedReference<ICorePlaybackObservation> {
     return this._src;
   }
 
@@ -110,7 +54,7 @@ export default class WorkerPlaybackObserver
   }
 
   public listen(
-    cb: (observation: IWorkerPlaybackObservation, stopListening: () => void) => void,
+    cb: (observation: ICorePlaybackObservation, stopListening: () => void) => void,
     options?: {
       includeLastObservation?: boolean | undefined;
       clearSignal?: CancellationSignal | undefined;
@@ -131,7 +75,7 @@ export default class WorkerPlaybackObserver
 
   public deriveReadOnlyObserver<TDest>(
     transform: (
-      observationRef: IReadOnlySharedReference<IWorkerPlaybackObservation>,
+      observationRef: IReadOnlySharedReference<ICorePlaybackObservation>,
       cancellationSignal: CancellationSignal,
     ) => IReadOnlySharedReference<TDest>,
   ): IReadOnlyPlaybackObserver<TDest> {