low audio volume when video calls connected across platforms

[b2bPrasad]

Specify the sample to which the issue belongs (use [x]):
[] Chat sample
[x] P2P Calls sample
[] Conference Calls sample

Platform (use [x])
[x] Android
[x] iOS
[] macOS
[x] Windows
[] Web
[] Linux

Device info
Manufacture:
Model:
OS version:

Describe the bug:
The volume when call is connected between users is low. This behavior is inconsistent and occurs across platforms.

[TatankaConCube]

can you reproduce it in our sample? what steps are for reproducing? we met some issues with the iOS platform, there was an issue with the conflict between the iOS system sound managing and the flutter_webrtc plugin. In the case the call was accepted from the Callkit from the killed state the sound was absent. The developer of the plugin added special methods for managing audio settings on the iOS side, you can try to call the following code after starting the a new call and after accepting it on the Flutter app side:

    if (Platform.isIOS) {
      Helper.setAppleAudioIOMode(AppleAudioIOMode.localAndRemote);
    }

Also, you can try to play with other configs using Helper.setAppleAudioConfiguration(). But I noticed that if select the AppleAudioMode.voiceChat as an AudioMode, the headphone output will be selected and you can switch to the speaker (and back), but if select the AppleAudioMode.videoChat the speaker will be selected and you will not switch to the headphone.