Clicking on HTPC audio recording

[Fat Tone]

My HTPC uses an AIW9800 to capture from my cable STB. I reconfigured it a couple of weeks ago (I sometimes use the inputs on the DVB-T card for tranfserring VHS which means swapping cables, plus MCE2005 'lost' the input at some point), including installing the latest ATi drivers.

It all works beautifully smoothly now (eg watching and recording at the same time is perfect, with good picture quality and no dropped frames or stuttering, which certainly wasn't the case in the past) BUT I am getting a popping noise only on the left audio channel once every 1 to 2 seconds.

Any suggestions what to check?

TIA.

[schmosef]

audio cable?

[schmosef]

[gt40]

cricket in your left ear?
Is it in the source? (swap the left and right cable, see if the popping follows it)
Tracking problems on the VCR?

[Fat Tone]

I just checked and it clicks even without an audio input cable connected. Seems to be on both speakers today.

[Fat Tone]

I've done all the usual checks. All drives are running in UDMA, plently of memory, CPU usage is ~50$, all other applications work as expected. The only problem the system has is clicking on the audio when viewing TV through the 9800 AIW in MCE.