No audio during recording

[Don]

I posted this problem a couple of weeks ago but did not get any responses and was wondering if anyone has heard of this problem. I have not had any problems when recording one show, the problem I have is when I record back to back shows. I tried recording Stargate last weekend when they played it for 12 straight hours. When I record the shows, I get no audio on a couple of the recordings. Everything works great for 1 or 2 shows then no audio. Then it records fine for a few shows then no audio. Anyone have any ideas???