what ken said and ......
we had a bit of splutter on our vp62/aac+ stream
first i put it down to hardware localy when this was eliminated as the cause,i checked buffer on the servers
and established that wasnt the problem.
Then i realised unlike other stations that use nsv/aac+
we stream using 32k v2 48000hz stereo sound which for some bizzare reason does not play back well on all viewers soundcards.
Ive personaly never had this problem even with crappy onboard soundcard on an old p3 machine.
also something you might want to look into is when you visit a website that contains flash this ive noticed,makes the sound choppy on aac+ streams.
Also third party plugins for winamp dsp and such
do crazy things to nsv streams when played back.
if you post which station in particular do this
then it might be much easyier to eliminate the problem