Reset tracked request value on failure

src/state/CallViewModel/localMember/Publisher.test.ts

@@ -212,12 +212,13 @@ describe("Publisher device sync", () => {
     selected$,
     capturedDeviceId,
     activeDeviceId,
+    switchActiveDevice = vi.fn().mockResolvedValue(true),
   }: {
     selected$: BehaviorSubject<SelectedInput>;
     capturedDeviceId?: string;
     activeDeviceId: string;
+    switchActiveDevice?: Mock;
   }): { publisher: Publisher; switchActiveDevice: Mock } {
-    const switchActiveDevice = vi.fn().mockResolvedValue(true);
     const livekitRoom = mockLivekitRoom({
       localParticipant,
       state: LivekitConnectionState.Connected,
@@ -294,6 +295,41 @@ describe("Publisher device sync", () => {
     await publisher.destroy();
   });
 
+  it("retries the same selection after a failed switch", async () => {
+    const selected$ = new BehaviorSubject<SelectedInput>(selectedInput(""));
+    const switchActiveDevice = vi
+      .fn()
+      .mockRejectedValueOnce(new Error("could not open the device"))
+      .mockResolvedValue(true);
+    const { publisher } = createDeviceSyncPublisher({
+      selected$,
+      // Pinned to the headset, so moving to the browser default is a switch
+      capturedDeviceId: "headset",
+      activeDeviceId: "headset",
+      switchActiveDevice,
+    });
+
+    expect(switchActiveDevice).toHaveBeenCalledTimes(1);
+    await flushPromises();
+
+    // The failed switch left us on the headset, so selecting the browser
+    // default again has to try once more rather than count as already done
+    selected$.next(selectedInput(""));
+    expect(switchActiveDevice).toHaveBeenCalledTimes(2);
+    expect(switchActiveDevice).toHaveBeenLastCalledWith(
+      "audioinput",
+      "default",
+      false,
+    );
+    await flushPromises();
+
+    // This time it worked, so there is nothing left to do
+    selected$.next(selectedInput(""));
+    expect(switchActiveDevice).toHaveBeenCalledTimes(2);
+
+    await publisher.destroy();
+  });
+
   it("does not switch when the room already captures from the selected device", async () => {
     const selected$ = new BehaviorSubject<SelectedInput>(
       selectedInput("headset"),

src/state/CallViewModel/localMember/Publisher.ts

@@ -392,6 +392,7 @@ export class Publisher {
         ) {
           return;
         }
+        const previousRequestedId = requestedId;
         requestedId = device.id;
         // For the browser default input, ask for "default" as a non-exact
         // constraint: browsers that have no such device ignore it and capture
@@ -399,9 +400,13 @@ export class Publisher {
         (browserDefaultInput
           ? lkRoom.switchActiveDevice(kind, "default", false)
           : lkRoom.switchActiveDevice(kind, device.id)
-        ).catch((e: Error) =>
-          this.logger.error(`Failed to sync ${kind} device with LiveKit`, e),
-        );
+        ).catch((e: Error) => {
+          // LiveKit keeps capturing from the previous device, so record that
+          // again to leave the next selection of this device something to do.
+          // A selection made while the switch was in flight wins, though.
+          if (requestedId === device.id) requestedId = previousRequestedId;
+          this.logger.error(`Failed to sync ${kind} device with LiveKit`, e);
+        });
       });
     };