Issue with media center in build 5728

I was watching recorded Tv shows in media center, this has always performed
very well.
However I have up to now never used the pause function
Today while I was watching recorded Tv the phone rang and I pressed pause, I
returned to finsh watching and pressed play to resume the show,
The show continued playing but without sound, I closed media center and
restarted it, and played the same recorded Tv show and the sound worked
again
After a bit of experimenting with it, I found that this was an issue with
all my recorded Tv shows. every one of them failed to have sound after
resuming from Pause


I see this as only being a minor issue seeing it's easily rectified by
restarting media center and it could well be related to my audio drivers
Has anyone else noticed this ?
I'd like to hear if anyone has had this issue so that I can confirm it's
either my drivers or vista causing this issue