Client upgraded to 6011 last year, then just recently the 65850E. All was fine for 3 weeks until one day they came home and their cable box didn't work. Resets didn't fix it nothing did. So I go out there and verify that it indeed does not work. All other sources did but not the cable box. (X1) firmware up to date on everything.

What is weird though is the cable box is obviously sending some sort of signal because the Marantz does not show up, the screen is black. As soon as you unplug the HDMI cable the Marantz logo shows on the screen. So I go through the usual steps. Different inputs, different cables. Swap this swap that. Nothing. I assume then it's The cable box but just to check I grab the clients other box and sure enough nothing. I literally brought every cable box in that house to the TV and same thing.

Of course cable box directly to TV works fine so temporarily I hooked it up. But that same day another client that's in the area emailed me and said he's got nothing either. (He's got a Marantz 5011) and now just today I have another client that says he's got the same issue. (Marantz 6011)

So what's going on here? Comcast updated something, but why is it effecting the Marantz's (I've moved to Sony since the spring of last year) all firmware alerts are turned off so I know the client isn't upgrading them. I issued it on the first clients AVR hoping it would fix it.

HDMI relay vs. HDMI repeater.

HDMI Control off on TV
HDMI Control off on the AVR
Use only Ethereal HDMI Cables
Put an HDMI Splitter between the cable box and AVR if that doesn't work, put if after the AVR.
Make sure you are not in the ARC HDMI on the TV. So on that TV don't be on HDMI 1.
What is between the AVR and TV? How long? HDBT?
Call Brent :)

On a very contorted system, because we must use Component distribution, we replaced the cable box because the older boxes no longer receive HD. We managed to come up with a box that offered Component output, but when I hooked things up there was a black screen. Obviously, there was some sync on the output or I would have seen a "no input" warning. The box was registered to the account, but during the conversation with the Comcast rep, there was a comment of "that's odd", followed by "wait a minute", a few reboots, then the video arrived.

It's HDMI 3 on the 65850E....

Literally can check off everything you said aside from call Brent. All cables are ethereal.

Very puzzling

See, shoulda stuck with Samsung 😜