HDMI/HDCP Signal Downgrade ?

I have an upconverting DVD player that is supposed to put out a 1080P signal over component and HDMI. My Mitsubishi WD-52631 HDTV is supposed to receive 1080P over the HDMI inputs. The best I can get is 1080I. When I try to get 1080P, I get a blue screen. I have read that other users of this player, Helios H4000, have connected to other HDTVs at 1080P.

My questions are: If this is this an HDCP issue, wouldn't the signal downgrade to 480P?

Since I'm getting 1080I is this an indication that all's well HDCP wise or does the secret handshake have various levels of downgrade?

Why would a device connect to one TV @ 1080P and only 1080I on mine??

When I questioned Mits about this, their last response was that I need to use HDMI 1.3 cables!! I wasn't aware that Mits had implemented 1.3 in the 2007 TV lineup yet. (I also wasn't aware that a "1.3" cable existed) Actually, it sounds like a "get this guy off the phone" response. Smoke!!

In another forum there is some chat about the Mits' sets will not accept a 1080P signal on their HDMI input #1, only on HDMI input#2. Could be true (until I can get the DVD player and the TV to talk I have no way of knowing) but it makes no sense. It seems that a goodly number of people are having 1080P connectivity issue with Mits sets.

Thank you for the response. However, the plot thickens.

I am in communication with the manufacturer of the DVD player and they recognize an incompatibility with the Mitsubishi sets. Even though I'm glad that they are working on a possible fix, based on other input in these forums, I tend to (very subjectively) believe that the problem is in the TV.

Which brings me to this evening. I'm watching an HD movie in 1080i, via a Comcast/Motorola 3412 STB to my Mitsubishi WD-52631 and up pops a box with a message that says something like this . "Your digital connection has been compromised. Switch to YPrPb." Something along those lines. The screen goes a swamp water green. Honest officer, I didn't do nuthin.

I switched things on and off, got back video, lost audio to my receiver. Shut everything down. Same thing. Did it again, good to go. Happened an hour ago. Since then, no problems. Any ideas?

Was it the cable box? HDTV? What happened. Is this the harbinger of things to come. The message box didn't say from whom the message was being sent.

My off the cuff comment is, HDMI is a good thing. Too bad it had to get hooked up with the piracy police. You know, the Keystone Cops.

I can at least try some things to get back up, or not. What does Granma do?