I have a hauppauge WinTV USB cap card and am using Virtual Dub 1.4.10 for capturing.

I use the WinTV2000 software to tune in the channel, which then appears in the virtual dub window. (Normal antenna going from video to cap card, and audio cable from cap card line out, to sound card line in)

But seemingly at random, WinTV2000 keeps on going into Mute mode, blocking the audio stream to virtual dub. When this happens, the audio is then heard through my TV speakers. If i click on mute off in WinTV2000, the sound via my TV stops, and it is audible again in Virtual Dub. But again, after a short while WinTV2000 mutes.

Anyone have any ideas why this may be happening?