I am new to the world of home theater and especially the use of hd projectors. I just received my optoma hd 20 projector a couple of days ago and I am having problems trying to connect it to my Comcast cable box( Motorola dcx 3400 with 25' hdmi cable). Whenever I connect the cable whether directly to the projector or through my receiver the image will appear for 5 seconds and then everything goes black. A faint white light is still coming out of the projector lens but nothing on the screen. If I manual switch inputs and go back the same thing happens. I have tried multiple cables and none seem to work. the blueray works fine. And I can get audio to the reciever from the cable box. Anyone have any ideas on how to remedy this?
Google the Motorola DCX 3400 cable box and you will find many references to EDID handshake problems. Try swapping out your cable box for something more recent...or invest in 25 feet of component cable.
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