diff --git a/src/state/MediaViewModel.ts b/src/state/MediaViewModel.ts
index 3da69c46..7f806697 100644
--- a/src/state/MediaViewModel.ts
+++ b/src/state/MediaViewModel.ts
@@ -257,10 +257,9 @@ abstract class BaseMediaViewModel {
      * The Matrix user to which this media belongs.
      */
     public readonly userId: string,
-    public readonly rtcBackendIdentity: string,
     // We don't necessarily have a participant if a user connects via MatrixRTC but not (yet) through
     // livekit.
-    protected readonly participant$: Observable<
+    protected readonly participant$: Behavior<
       LocalParticipant | RemoteParticipant | null
     >,
 
@@ -407,8 +406,11 @@ abstract class BaseUserMediaViewModel extends BaseMediaViewModel {
     scope: ObservableScope,
     id: string,
     userId: string,
-    rtcBackendIdentity: string,
-    participant$: Observable<LocalParticipant | RemoteParticipant | null>,
+    /**
+     * The expected identity of the LiveKit participant. Exposed for debugging.
+     */
+    public readonly rtcBackendIdentity: string,
+    participant$: Behavior<LocalParticipant | RemoteParticipant | null>,
     encryptionSystem: EncryptionSystem,
     livekitRoom$: Behavior<LivekitRoom | undefined>,
     focusUrl$: Behavior<string | undefined>,
@@ -421,7 +423,6 @@ abstract class BaseUserMediaViewModel extends BaseMediaViewModel {
       scope,
       id,
       userId,
-      rtcBackendIdentity,
       participant$,
       encryptionSystem,
       Track.Source.Microphone,
@@ -677,7 +678,7 @@ export class RemoteUserMediaViewModel extends BaseUserMediaViewModel {
     id: string,
     userId: string,
     rtcBackendIdentity: string,
-    participant$: Observable<RemoteParticipant | null>,
+    participant$: Behavior<RemoteParticipant | null>,
     encryptionSystem: EncryptionSystem,
     livekitRoom$: Behavior<LivekitRoom | undefined>,
     focusUrl$: Behavior<string | undefined>,
@@ -779,8 +780,7 @@ export class ScreenShareViewModel extends BaseMediaViewModel {
     scope: ObservableScope,
     id: string,
     userId: string,
-    rtcBackendIdentity: string,
-    participant$: Observable<LocalParticipant | RemoteParticipant>,
+    participant$: Behavior<LocalParticipant | RemoteParticipant>,
     encryptionSystem: EncryptionSystem,
     livekitRoom$: Behavior<LivekitRoom | undefined>,
     focusUrl$: Behavior<string | undefined>,
@@ -793,7 +793,6 @@ export class ScreenShareViewModel extends BaseMediaViewModel {
       scope,
       id,
       userId,
-      rtcBackendIdentity,
       participant$,
       encryptionSystem,
       Track.Source.ScreenShareAudio,
diff --git a/src/state/ScreenShare.ts b/src/state/ScreenShare.ts
index e4f5de1f..6c908b1f 100644
--- a/src/state/ScreenShare.ts
+++ b/src/state/ScreenShare.ts
@@ -4,7 +4,7 @@ Copyright 2025 New Vector Ltd.
 SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
-import { of } from "rxjs";
+
 import {
   type LocalParticipant,
   type RemoteParticipant,
@@ -14,7 +14,7 @@ import {
 import { type ObservableScope } from "./ObservableScope.ts";
 import { ScreenShareViewModel } from "./MediaViewModel.ts";
 import type { EncryptionSystem } from "../e2ee/sharedKeyManagement.ts";
-import type { Behavior } from "./Behavior.ts";
+import { constant, type Behavior } from "./Behavior.ts";
 
 /**
  * A screen share media item to be presented in a tile. This is a thin wrapper
@@ -28,7 +28,6 @@ export class ScreenShare {
     private readonly scope: ObservableScope,
     id: string,
     userId: string,
-    rtcBackendIdentity: string,
     participant: LocalParticipant | RemoteParticipant,
     encryptionSystem: EncryptionSystem,
     livekitRoom$: Behavior<LivekitRoom | undefined>,
@@ -41,8 +40,7 @@ export class ScreenShare {
       this.scope,
       id,
       userId,
-      rtcBackendIdentity,
-      of(participant),
+      constant(participant),
       encryptionSystem,
       livekitRoom$,
       focusUrl$,
diff --git a/src/state/UserMedia.ts b/src/state/UserMedia.ts
index 74d24e2f..2adc9134 100644
--- a/src/state/UserMedia.ts
+++ b/src/state/UserMedia.ts
@@ -143,7 +143,6 @@ export class UserMedia {
                     scope,
                     `${this.id}:${key}`,
                     this.userId,
-                    this.rtcBackendIdentity,
                     p,
                     this.encryptionSystem,
                     this.livekitRoom$,
diff --git a/src/state/layout-types.ts b/src/state/layout-types.ts
index 3796715c..f32869df 100644
--- a/src/state/layout-types.ts
+++ b/src/state/layout-types.ts
@@ -10,6 +10,8 @@ import {
   type SpotlightTileViewModel,
 } from "./TileViewModel.ts";
 import {
+  type LocalUserMediaViewModel,
+  type RemoteUserMediaViewModel,
   type MediaViewModel,
   type UserMediaViewModel,
 } from "./MediaViewModel.ts";
@@ -40,8 +42,8 @@ export interface SpotlightExpandedLayoutMedia {
 
 export interface OneOnOneLayoutMedia {
   type: "one-on-one";
-  local: UserMediaViewModel;
-  remote: UserMediaViewModel;
+  local: LocalUserMediaViewModel;
+  remote: RemoteUserMediaViewModel;
 }
 
 export interface PipLayoutMedia {