Sounds like the TV is loosing the HDCP sync or your HTPC send the graphic to sleep, because not monitor is detected. Look for a firmware update for your TV.
Thanks for the quick reply; would that explain the fact that the signal comes back when remove the non-htpc device. and that the signal is lost only when I cycle between inputs.
Although I say that the signal is lost, what really happens is when I cycle to htpc the second time, I get a grained white noise kind of screen with lots of static
The TV does have the latest firmware; also I didnt have this problem when I had a different computer connected earlier; that was a gigabyte MB with AMD processor. I dont know whether I am making things more confusing, but this is just driving me nuts