We have a Web App that uses WebRTC 2 way audio. After upgrading to iOS 15 the output audio to speakers (or bluetooth with AirPods) is about 2/3 reduced. The microphone outgoing audio is fine. This has been reproduced on iPhone 7 and iPhone XS.
It can be reproduced by going to:
https://webrtc.github.io/samples/src/content/getusermedia/audio/
or
https://appr.tc/
If you compare the playback audio level of an iPhone XS running 15.x, you will find it is about 2/3 volume as an iPhone XS running 14.8.
Our web App has been running fine with good audio levels since 2018 and iOS 11.x.
marcusgilson
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