I'm getting the same issue. I'm on a HTC Desire running Andriod 2.2, connected via mobile network (not WiFi) and on the o2 UK network. My feed shut off after about 45seconds using the default Android player.
Interestingly, it seems to be only on Mobile Internet the problem arises. I ran a feed for 5mins on WiFi without issue. (It didn't fail after 5mins, I switched it off).
I would definitely suggest it's a mobile internet problem. It's a shame as I'd like to be able to use it on the move!