[Bug] Mic sound is not streamed from MacOS browsers to UE app

[DenisTensorWorks]

Originally opened by @vlobzakov

UE Version:
E.g. UE 5.1.1+

Frontend Version:
UE5.1+

Problem component
Signalling Server WebRTC

Description
Sound capture via microphone doesn't work for MacBooks

Steps to Reproduce:

1. Build UE application that should record voice via Microphone.
2. Stream UE application via Pixelstreaming.
3. Open Stream on Macbook in Chrome or Safari.
4. Speak.
5. Check UE app what does it recieve(record) via browser.

Expected behavior

1. On Windows/Linux any browser can interact with UE via Pixelstreaming doing sound recordings.

Screenshots

Platform (please complete the following information):

• OS: MacOS that comes with MacBook Intel, MacBook M1 and MacBook M2.
• Browser Chrome 90+ and Safari

Additional context
In case of Chrome you can record sound with help of webrtc-internals and store it locally. Then yoou can play these files and listen that Chrome does recording properly. But sound from microphone isn't streamed to UE app.
If Pixelstreaming service taken from branch 5.0 this bug is not available and UE app can record sound from browser properly.

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Moved from EpicGames/PixelStreamingInfrastructure#494

[varunshankar09]

were you able to solve this? I can neither send mic input, nor receive audio output.

[zhongl]

Try option -PixelStreamingWebRTCDisableReceiveAudio=false.
See https://dev.epicgames.com/documentation/en-us/unreal-engine/unreal-engine-pixel-streaming-reference#webrtcconfiguration for more information.