Our project on iOS 15 stops playing sound after being restored from the running in the background for more than 5 seconds or so. This happens in our existing project, but also happens on the off-the-shelf side scroller project in Unreal - after attaching a sound to a “jump” action on the character. This issue does not happen on iOS 14 or lower.
Interestingly enough, the Unreal Match 3 sample game available in the store exhibits the exact same behaviour. Has anyone else experienced this and/or have any hints for resolution?
I filed a bug with Unreal when I first posted, but no response from them. I’ve since ported all our audio to use FMOD. Problems are gone - use their audio engine instead of Unreal’s.
Sorry, no bug number - I submitted the bug on Sept 22 and only got this:
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Thank you,
Epic Games
iOS 15 got released after 4.27 Release so QA did not see this issue.
We have looked into it and found out AVAudioSessionInterruptionTypeKey behavior has changed in iOS15, so we stopped relying on it altogether to make sure sound works on all iOS versions.
I have tested the change on iOS13.5 and iOS15.1 with a template project and it works as expected, but please understand QA has yet to make a pass on this code so I cannot attest of its reliability for now.
We are trying to get it in 4.27.2.
If you want to merge it to your current engine, here is a patch that needs to be applied to
Engine/Source/Runtime/ApplicationCore/Private/IOS/IOSAppDelegate.cpp
