Try this forum instead.
My PVR-350 does the same thing after starting recording sometimes. The audio is always about a second out of sync then too - pressing the ¦¦button in the Record section of the window and then the Play button gets the audio back in sync.
I'm not overly impressed with Hauppauge's drivers. Their original PVR card, the PVR-PCI, was nice. No delay at all in the TV window so you could game if you wanted to, with an Xbox or whatever, which translated to very low CPU usage too, since it wasn't constantly decoding an MPEG2 stream. But it was plagued with other problems, until they eventually just gave up on it and did a redesign with the PVR-250, then the 350, and now the 150 and 500 which, as you can tell, still have some problems. I'm wary that they've left the 250 and 350 behind now, as there haven't been any driver updates for them in a year.