Show not recording

Okay, I'm having another problem. I had the HWS for a few weeks.

I recorded the golf, about an hour the recording goes black.
Also I record nascar, it shows 4 hr recording, but stop after about an hour.

The actual time of stoping I do no know or if I can reproduce this.

Is this another problem being work on?

Thanks

Okay there is a problem with hws. I recorded nascar, started watch it before the end of recording, in the middle its started recording a black screen, also try it on the super Joey, when black at the same time (lap).
Then I try to view the channel, it's was black, also try on the SJ, it was black.
Then I notice the nascar was still recording, so I stop the recording, and the channel came back.

So, what going on, and is there a fix or work around ?

Thanks