Bug 208233
| Summary: | Audio crackling in WebRTC calls on iOS using Cisco Meeting WebRTC app | ||
|---|---|---|---|
| Product: | WebKit | Reporter: | mawojtcz |
| Component: | WebRTC | Assignee: | Nobody <webkit-unassigned> |
| Status: | RESOLVED CONFIGURATION CHANGED | ||
| Severity: | Critical | CC: | milen.yordanov, webkit-bug-importer, willwoo, youennf |
| Priority: | P2 | Keywords: | InRadar |
| Version: | Safari 13 | ||
| Hardware: | iPhone / iPad | ||
| OS: | iOS 13 | ||
mawojtcz
When joining calls using Cisco Meeting WebRTC app in Safari on iPhones the user can hear audio crackling. The crackling is heard on different iPhone models (for example: 7s, XR) and different iOS versions (both 12.x and 13.x)
Here at Cisco, we have created a temporary account in our product that should allow you to replicate the issue we are seeing. I can provide you a link to it if you message me privately, as we don't want this link to be available in public.
We've done some initial investigation on this and these are our findings:
- Audio plays fine in our product without any crackling in Chrome and Firefox on Windows and MacOS as well as Safari on MacOS and Chrome on Android
- The issue is intermittent. Sometimes the audio may work fine for a long period of time and on another occasion the crackling will be very frequent. It seems that the probability of crackling gets higher with longer time since the phone's reboot or when more apps have been used. Once it starts, it seems to be worse when the app is doing some UI transitions etc.
- When we capture the network traffic and recreate the audio from the pcap file, we don't hear the crackling in the resultant wav file
- When we've modified our werbtc app to not do any video encoding and decoding, we could still hear the audio crackling
- Audio crackling can be heard also when we tried other audio codecs
| Attachments | ||
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| Add attachment proposed patch, testcase, etc. |
Radar WebKit Bug Importer
<rdar://problem/59802870>
youenn fablet
bug 210107, bug 209969, bug 210052, and bug 210180 are helping reducing the audio crackling according our testing.
If the device is doing intensive processing, there might still be some audio drop outs. This might also happen when page is scrolling, given the WebRTC audio thread priority is the same as the scrolling one.
Closing the bug based on above bugs being fixed.
youenn fablet
https://bugs.webkit.org/show_bug.cgi?id=211720 will also help removing audio crackling when piping a media stream into WebAudio.
youenn fablet
https://bugs.webkit.org/show_bug.cgi?id=212132 is another one that will help in case web audio is used to analyse media streams