I am by no means an expert on this topic, but I also collect a live stream to start and stop at a specific time. I don't know about the audio issue, but here is my code, maybe this will help you a bit.
at 2014-05-23 10:00
cvlc "http://*My url to video stream*" --sout file/mp4:*THEFILENAMEYOUCHOOSE*.mp4 --run-time=300 --stop-time=300 vlc://quit
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