It is the card losing interrupts but this was fixed after 2.6.11 kernel on my machine. I am running FC4 kernels now.
As far as I can see, it is not a driver problem in my case, given that a restart of vdr suffices to get the problem solved. I don't need to reload my drivers.
It is a xine problem because VDR will still record in this state. Now I have xine showing NO SIGNAL after long periods of inactivity because SetPlayMode: switched to 0. Just zapping to a channel wakes xine.
I've never seen this problem on my box.
Thank you for posting anyway.
Best regards,
Maarten