Bug 255949

Summary: AudioContext huge crackling/pops sound during user actions - iPadPro iOS 16.4.1 - Mac Silicon M1
Product: WebKit Reporter: Faks <faksprod>
Component: Web AudioAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Major CC: cdumez, jer.noble, webkit-bug-importer, youennf
Priority: P2 Keywords: InRadar
Version: Safari 16   
Hardware: iPhone / iPad   
OS: iOS 16   

Description Faks 2023-04-25 12:59:11 PDT
Huge pops/crackling sounds when user interact with the DOM during Audio Context is running and playing a buffer node.
How to reproduce it:

- iPadPro 1st gen (2015) with iOS 16.4.1
- From Safari on the device go to this link https://stackblitz.com/edit/web-audio-api-sandbox?file=index.js
- On the right preview code panel click the buttons to play sounds
- During sound is playing, interact with the DOM (for example scroll up and down the code section)
-> you will ear huge and dirty crackling sounds

You can check a screen record here https://www.youtube.com/watch?v=OrSpwUBZfnQ
(of course the speakers on this device are totally fine).

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It looks like similar to another one you can reproduce from Mac Silicon M1

- Mac M1 running on Ventura 13.3.1
- From Safari Technology Preview go to this link https://stackblitz.com/edit/web-audio-api-sandbox?file=index.js
- On the right preview code panel click the buttons to play sounds
- Interact with the page (or change you volume up/down by touching your keyboard)
-> you will ear huge and dirty crackling sounds

You can check a screen record here https://www.youtube.com/watch?v=CT7oYQj71go
(of course the speakers on this Mac are totally fine).

---------------------------------
I work on a JS musical app since 8 years targeting iOS/Android/MacOS/Windows (Cordova/Electron based project using webview in native app)
Such a bug (which I already encountered several times by the past) only occurs on Safari and/or Safari Webview.

Some iOS releases have fixed the bug, then after other iOS releases, the bug comeback again, then later is fixed again, then come back...
It is a real user experience killer for JS apps using Web Audio API.

I hope these examples may help the dev team. Thanks for your work and time.
Comment 1 Radar WebKit Bug Importer 2023-04-25 18:34:30 PDT
<rdar://problem/108535809>
Comment 2 Smoley 2023-05-04 13:40:36 PDT
Thanks for filing, I've not been able to reproduce this so far on macOS or iOS. Can you please file a report at feedbackassistant.apple.com and include a sysdiagnose in that report? It would also be helpful to mention this bugzilla report as well so we can associate the two. Thanks again.