Bug 219161

Summary:	Crackling Audio noise
Product:	WebKit	Reporter:	Mish <mish>
Component:	Web Audio	Assignee:	Nobody <webkit-unassigned>
Status:	REOPENED ---
Severity:	Major	CC:	ap, cdumez, mish, webkit-bug-importer, youennf
Priority:	P2	Keywords:	InRadar
Version:	Safari 14
Hardware:	iPhone / iPad
OS:	All

Description Mish 2020-11-19 07:42:18 PST

Hello,
we're building a web application which listens to microphone and plays audio responses via Web Audio API

on the iOS the Audio is starting to crackle and make noises
we've noticed some patterns that are contributing to the noises

- Older device or low-power mode
- Microphone is allowed (could be unrelated)
- Only on iOS

testing was done on

- iPhone 7 Plus, iOS 14.1, 14.2

this bug makes a very bad listening experience for our users

Comment 1 Alexey Proskuryakov 2020-11-19 18:54:27 PST

This sounds much like bug 218762. Could you please try iOS 14.3 developer beta 2?

If you still observe issues, please reopen with test cases, as the report is not actionable with a way to reproduce.

Comment 2 Mish 2020-11-20 11:36:18 PST

Hello Alexey

please check the video
https://www.youtube.com/watch?v=RPy7pZsfelE

listen closely and notice what happens to audio when i activate/deactivate microphone

check demo yourself: https://gh.mish.co/dialogflow-web-v2
type: "Help me"

the video was taken on iPhone 7 Plus in low-power mode on iOS 14.2

Comment 3 Mish 2020-11-20 11:37:30 PST

my client is having same issue on iPhone XR on iOS 13.7

Comment 4 Mish 2020-11-20 11:53:36 PST

here is a video confirmation from my client
(iPhone XR, iOS 13.7)

https://i.imgur.com/zNWaqiG.mp4

again, listen what happens when he toggles microphone

Comment 5 Alexey Proskuryakov 2020-11-20 13:25:30 PST

Could you please try iOS 14.3 developer beta 2?

Comment 6 Mish 2020-11-21 07:45:40 PST

Alexey
i tried iOS 14.3 public beta 2

sadly, no improvements

i hear no cracks when microphone is disabled, but as soon as i allow the microphone the quality drops significantly

given the application we're building is voice-only, our customers will hear corrupted audio all the time

competitor application we evaluated is also suffering from the same issue

what should we do now?

Comment 7 Alexey Proskuryakov 2020-11-21 19:54:52 PST

Thank you for the test case!

I could reproduce with iPhone 7, using
- iOS 14 (18A373);
- iOS 14.2 (18B92);
- iOS 14.2 beta 2 (18C5054c).

There is very substantial crackling noise indeed. I was initially confused because I could hear very minor crackling at the end of some sentences on iPhone 12 Pro, but things are much worse on iPhone 7, especially in the mode you suggested (microphone on, low power mode).

Comment 8 Radar WebKit Bug Importer 2020-11-21 19:55:05 PST

<rdar://problem/71661504>