Sleep Timer and Pandora/third party music apps

I was thrilled to discover the sleep timer function of the clock app, as it lets me use the touch (hooked up to speakers) to listen to music as I drift off to sleep.

However it doesn't seem to be working (at least not consistently) with my Pandora app. I set the sleep timer last night, then turned went to the Pandora app. I fell asleep, but woke up at 5 a.m. and the music was playing. My husband says it played most of the night.

I did search the forums; the one possibility I found was that perhaps I had "push" on and should turn it off. I'm not entirely sure what that means. The Push settings for mobile me? Or for some other app? (I have the new Facebook app update with push notifications).

thanks,

kabing