Bug 249004

Summary: Audio bitrate drops after 5 minutes
Product: WebKit Reporter: Teodor <teodor.atroshenko>
Component: WebRTCAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: webkit-bug-importer, youennf
Priority: P2 Keywords: InRadar
Version: Safari 16   
Hardware: Mac (Apple Silicon)   
OS: macOS 13   
Attachments:
Description Flags
Audio bitrate graph
none
Audio packet count graph none

Description Teodor 2022-12-08 19:23:09 PST
Created attachment 463949 [details]
Audio bitrate graph

During multi-party WebRTC call (SFU), the issue was encountered when using RODECaster Pro Stereo microphone, opus/48000/2 codec, with minptime=10;useinbandfec=1 parameters. After around 5 minutes since the peer connection is established, the audio bitrate drops significantly and static noise is introduced. Packet count is consistent with no other issues (e.g., no video quality or data channel issues). Attached are screenshots of audio bitrate and packet count graphs, with bitrate drop happening around the time when the person resumes speaking after a pause in speech. This issue is consistently reproducible in Safari, yet does not happen in Chrome on the same device.
Comment 1 Teodor 2022-12-08 19:23:38 PST
Created attachment 463950 [details]
Audio packet count graph
Comment 2 Radar WebKit Bug Importer 2022-12-15 19:24:18 PST
<rdar://problem/103429762>