I'm having audio problems with my feed,all i'm hearing is a loud hum with distorted or no audio when i listen on windows media player.when i unmute my line in or mic i hear the audio fine but still has the loud hum.
I'm sure you have covered all of this, but try it again and see.
Record from the Mic input on your sound card, Mic works better for most cards. Headphones out to Mic in. Be sure your Audio controls in Windows also are showing Mic as the input. Turn your scanner volumn down to 1/2 or slightly less, If your using OddCast, be sure the slider is down to half to one quater. Also be sure oddcast see's that your recording from the Mic. in your Audio card controls, turn your Mic down to 25% and do not monitor.
I got some humming when I first attempted to run a feed. For me, I had to be sure all properties were seeing the Mic and then turn down the recording levels.
I think ScannerKid might be able to diagnose your problem better and help you find a resolve if the above dosn't work.