I've recently started having an issue with my TV. I had the white dot issue and replaced the DLP chip a couple of years ago - everything has been great since then until about a month ago.
On both HDMI 1 and 2 (which are connected to our Dish DVR and AppleTV respectively), The TV will randomly appear to turn off, then turn back on with no signal. In the case of the Dish box on HDMI 1, it takes a couple of seconds, and then finds the signal and goes on with life. In the case of the AppleTV on HDMI 2 it never finds the signal again unless I power cycle the AppleTV.
When it first started happening, I thought maybe there was a problem with the HDMI cable, since it was only happening on the AppleTv. Replacing that did nothing and now it's happening on the other input.
This usually happens about once every 3-4 days or so, but this weekend it happened about 4-5 times within an hour while watching the Dish DVR.
Any ideas what is causing this?