I'm using a gen 4 iPad with iOS 7 and I've noticed that the Play/Pause and Fwd/Back controls bottom left and the volume controls bottom right disappear after a while. Looks like this happens after I've switched to another application temporarily. The Core Control app still has the play queue, the Focus I had set and is tracking with whatever track is playing.

I have not experienced this before with iOS 6 on the same iPad. Is anyone else seeing this?

Sergio