Originally Posted by gwvideo
We are seeing it in HD and SD. When we run it through component it's fine but both HDMI inputs bug out after a few seconds on both HD and SD channels
HDMI handshake problems between cable boxes and projectors are more common than they should be. Personally I run component from my Time Warner Cisco cable box to the AR100U mainly because I've always used this connection. I've tried both HDMI and component cables and I can't really see a quality difference, they both carry 720p and 1080i. But I also have a 45 foot run of HDMI cable from my Denon AVR to the projector with no problems. I feed multiple devices through the AVR - 2 Blu-ray players, 3 streamers - the Roku 3, Apple TV 3 and the WDTV Live.
How long is the HDMI cable?
Is the HDMI cable verified high speed?
What is the make and model of the Comcast cable box?
Do you run the HDMI cable direct from the cable box to the projector or is it routed through an AVR?
Things I would do:
Eliminate the HDMI inputs on the AR100U as the problem. Run a shorter HDMI cable (6 feet) direct from a Blu-ray player to the AR100U.
Do you get a stable picture? If yes, then the HDMI inputs are okay.
Run the HDMI cable direct from the cable box to the AR100U, bypassing any switcher like an AVR.
Do you get a stable picture? If yes, then the AVR may be the problem.
Try changing the output resolution on the cable box to the lowest possible quality like 480p or 480i.
Do you get a picture? If yes, then the problem may lie with your HDMI cable.
These are just a few of the trouble-shooting tips I could think of right now.