no video/audio detected on analog channels (1 Viewer)

[Nippywiffle]

TV-Server Version: 0.3 SVN 16993
MediaPortal Version: 0.2.3 SVN 16993
MediaPortal Skin: Blue
Windows Version: XP SP2
CPU Type: Athlon xp 3200+
HDD: sata 500 + 200gb
Memory: 768mb
Motherboard: abit an7
Motherboard Chipset: nvidia nforce
Video Card: Nvidia geforce 6800gt
Video Card Driver: latest
Sound Card: onboard nvidia
Sound Card AC3: optical
Sound Card Driver: latest
1. TV Card: Hauppauge hvr-1600
1. TV Card Type: atsc/analog hybrid
1. TV Card Driver: latest

I just upgraded to the latest version 16993, hoping it may solve someof my timeshift problems, but I now have a new problem - none of my analog channels work. QAM HD channels work fine.

I get "No Video/Audio detected" when trying to view, or preview the analog channels, which worked fine on the version I was using before - SVN 16622

I tried re-scanning for analog channels, and it found them all again, but when I preview, it still says "no audio/video detected"

Is this a known issue? Something must have changed between my old svn 16622 and the new one 16993.

Thanks,
Dan