Audioservices volume issue on 4th gen. iPod touch

I am currently developing a game for iPhone/iPod touch. For short sounds I am using the AudioServicesPlaySystemSound function. I know that I can't control the volume of these sounds programmatically, but on my iPod touch 3rd gen 开发者_如何转开发these sounds respect the overall sound volume. On my new iPod touch 4th gen, these sounds are always played at the same volume, no matter to which value the overall volume is set. They even play if the volume is turned down to 0. The AVAudioPlayer on the other hand works as expected. Both devices are upgraded to iOS 4.1.

Has anyone else noticed this? Any suggestions what's happening here?

Just in case someone has the same issue / is interested: If you have an AVAudioPlayer playing at the same time, this problem goes away, that means, the systemsounds behave correctly again. In my case I play an empty mp3 in an infinite loop now. Not the nicest solution but one that works.

Has anyone else noticed this?

Yes, also for AudioServicesPlaySystemSound. It happens on my iPod touch 4G, but not my iPhone 3G. Both also running iOS4.1.

I've no idea what's happening, but I'll offer a bounty try to get some helpful uberguru's attention. If not, 1 infinite loop it is.

Update: apparently the problem also happens with AVAudioPlayer on the iPod 4th Gen - see https://devforums.apple.com/message/333169

It looks like it might be a bug. We'll see...