Firefox audio output issues fix (#1510)

---------

Signed-off-by: Timo K <toger5@hotmail.de>

src/livekit/MediaDevicesContext.tsx

@@ -28,6 +28,7 @@ import { createMediaDeviceObserver } from "@livekit/components-core";
 import { Observable } from "rxjs";
 
 import {
+  isFirefox,
   useAudioInput,
   useAudioOutput,
   useVideoInput,
@@ -65,7 +66,8 @@ function useObservableState<T>(
 function useMediaDevice(
   kind: MediaDeviceKind,
   fallbackDevice: string | undefined,
-  usingNames: boolean
+  usingNames: boolean,
+  alwaysDefault: boolean = false
 ): MediaDevice {
   // Make sure we don't needlessly reset to a device observer without names,
   // once permissions are already given
@@ -86,18 +88,19 @@ function useMediaDevice(
   const available = useObservableState(deviceObserver, []);
   const [selectedId, select] = useState(fallbackDevice);
 
-  return useMemo(
-    () => ({
+  return useMemo(() => {
+    const devId = available.some((d) => d.deviceId === selectedId)
+      ? selectedId
+      : available.some((d) => d.deviceId === fallbackDevice)
+      ? fallbackDevice
+      : available.at(0)?.deviceId;
+
+    return {
       available,
-      selectedId: available.some((d) => d.deviceId === selectedId)
-        ? selectedId
-        : available.some((d) => d.deviceId === fallbackDevice)
-        ? fallbackDevice
-        : available.at(0)?.deviceId,
+      selectedId: alwaysDefault ? undefined : devId,
       select,
-    }),
-    [available, selectedId, fallbackDevice, select]
-  );
+    };
+  }, [available, selectedId, fallbackDevice, select, alwaysDefault]);
 }
 
 const deviceStub: MediaDevice = {
@@ -120,10 +123,17 @@ interface Props {
 }
 
 export const MediaDevicesProvider: FC<Props> = ({ children }) => {
-  // Counts the number of callers currently using device names
+  // Counts the number of callers currently using device names.
   const [numCallersUsingNames, setNumCallersUsingNames] = useState(0);
   const usingNames = numCallersUsingNames > 0;
 
+  // Use output device names for output devices on all platforms except FF.
+  const useOutputNames = usingNames && !isFirefox();
+
+  // Setting the audio device to sth. else than 'undefined' breaks echo-cancellation
+  // and even can introduce multiple different output devices for one call.
+  const alwaysUseDefaultAudio = isFirefox();
+
   const [audioInputSetting, setAudioInputSetting] = useAudioInput();
   const [audioOutputSetting, setAudioOutputSetting] = useAudioOutput();
   const [videoInputSetting, setVideoInputSetting] = useVideoInput();
@@ -136,7 +146,8 @@ export const MediaDevicesProvider: FC<Props> = ({ children }) => {
   const audioOutput = useMediaDevice(
     "audiooutput",
     audioOutputSetting,
-    usingNames
+    useOutputNames,
+    alwaysUseDefaultAudio
   );
   const videoInput = useMediaDevice(
     "videoinput",
@@ -150,7 +161,9 @@ export const MediaDevicesProvider: FC<Props> = ({ children }) => {
   }, [setAudioInputSetting, audioInput.selectedId]);
 
   useEffect(() => {
-    if (audioOutput.selectedId !== undefined)
+    // Skip setting state for ff output. Redundent since it is set to always return 'undefined'
+    // but makes it clear while debugging that this is not happening on FF. + perf ;)
+    if (audioOutput.selectedId !== undefined && !isFirefox())
       setAudioOutputSetting(audioOutput.selectedId);
   }, [setAudioOutputSetting, audioOutput.selectedId]);
 

src/room/GroupCallView.tsx

@@ -224,7 +224,8 @@ export function GroupCallView({
 
       leaveRTCSession(rtcSession);
       if (widget) {
-        // we need to wait until the callEnded event is tracked. Otherwise the iFrame gets killed before the callEnded event got tracked.
+        // we need to wait until the callEnded event is tracked on posthog.
+        // Otherwise the iFrame gets killed before the callEnded event got tracked.
         await new Promise((resolve) => window.setTimeout(resolve, 10)); // 10ms
         widget.api.setAlwaysOnScreen(false);
         PosthogAnalytics.instance.logout();

src/settings/SettingsModal.tsx

@@ -35,6 +35,7 @@ import {
   useDeveloperSettingsTab,
   useShowConnectionStats,
   useEnableE2EE,
+  isFirefox,
 } from "./useSetting";
 import { FieldRow, InputField } from "../input/Input";
 import { Button } from "../button";
@@ -130,7 +131,8 @@ export const SettingsModal = (props: Props) => {
       }
     >
       {generateDeviceSelection(devices.audioInput, t("Microphone"))}
-      {generateDeviceSelection(devices.audioOutput, t("Speaker"))}
+      {!isFirefox() &&
+        generateDeviceSelection(devices.audioOutput, t("Speaker"))}
     </TabItem>
   );
 

src/settings/useSetting.ts

@@ -58,8 +58,12 @@ export const getSetting = <T>(name: string, defaultValue: T): T => {
 export const setSetting = <T>(name: string, newValue: T) =>
   setLocalStorageItem(getSettingKey(name), JSON.stringify(newValue));
 
-const canEnableSpatialAudio = () => {
+export const isFirefox = () => {
   const { userAgent } = navigator;
+  return userAgent.includes("Firefox");
+};
+
+const canEnableSpatialAudio = () => {
   // Spatial audio means routing audio through audio contexts. On Chrome,
   // this bypasses the AEC processor and so breaks echo cancellation.
   // We only allow spatial audio to be enabled on Firefox which we know
@@ -69,7 +73,7 @@ const canEnableSpatialAudio = () => {
   // widely enough, we can allow spatial audio everywhere. It's currently in a
   // chrome flag, so we could enable this in Electron if we enabled the chrome flag
   // in the Electron wrapper.
-  return userAgent.includes("Firefox");
+  return isFirefox();
 };
 
 export const useSpatialAudio = (): DisableableSetting<boolean> => {