Hello, I’ve been having some issues at one of my latest installs, and I can’t seem to figure out the issue. We’ve installed a 7.1 surround using an Integra DRX 3.2, an Epson 6040, 4K Apple TV and xfinity x1 cable box. The issues that we are having, is they while on Xfinity the picture seems to glitch along with the audio from time to time. The issues are only happening with Xfinity and not Apple TV. We are using a 4K fiber hdmi cable, but we have replaced it with a 4K HDMI Balun and having same issues. We have replaced the cable box, the 6ft hdmi cable from the cable box to the receiver, and even switched inputs on the AV receiver from cbl/sat to BD/dvd and still having issues. Does anyone know what can be causing this? Thanks

As a test, run a coax overland and connect the cable box directly to the TV.

Sometimes you can call Comcast and have them interrogate the box.

Does it always glitch on the same channel?

That was going to be my next step. I’ve got a feeling that the signal might be sufficient going to that cable box. The issue happens with different channels ex: Tnt, espn, abc, hbo etc

This is a link to the video that I took of the glitching


[Link: drive.google.com]

If you dig around, some of the cable boxes will give a signal level report. However, it is a static report at a point in time. You might get lucky and catch an intermittent signal drop if this is the issue.

If you put the cable box into 1080p, 30hz, stereo audio EDID mode, do you get the same issues or is it only at the higher bandwidth EDID settings ?

I would start with a low setting and change the EDID up one notch at a time.

Obviously you would need to do this on a high bandwidth video, like a 4k movie.

I’ve had Tons of issues with Comcast cable boxes over the last month. Had over 20 hours of billed service time due to bad newly installed boxes in 3 different houses.

Some wouldn’t even give a video when installed at all. Had one drive a matrix switch insane when connected.

Seems like they don’t test them at all before sending them out.

Do you have a small TV that can be placed near the cable box and connected via a short HDMI cable? Try that and if it still does this, connect a component or composite cable. If it still does it, return the cable box, but make sure the connections from the demarc point to the cable box are good, the ends are terminated properly and you don't need a DC block on the feed.

I'm having the same problems with Spectrum boxes- I'm not sure they do anything beyond making sure the lights go on with power and when they press the power button. It's the equivalent to checking for human life by seeing if they can fog a spoon.

Probably, they send the boxes out and track the serial numbers. When a box is returned, the assumption is probably "operator error" or incompetent field staff. If the same box comes back multiple times with a complaint, they will then send it out for repair or destruction.

^^This for sure. A test monitor at the cable box should at least tell you cable box or receiver (it is related to onkyo). Also, you didn't mention what brand the fiber HDMI was. I have not used any of them out there, but I have had great luck with the high end Ethereal active-super-ultra-Velox. (though I don't know your run length or if there's Carlon available)

As a Minnesota guy, could it just be the Timberwolves? LOL, sorry...

Also, on the cable line, is there a powered Commscope splitter involved?

At the end of August last year I received an email from the Australian distributor of Denon and Marantz regarding problems with the new Foxtel (Australian Pay TV provider) IQ4 4K set top boxes. These involve HDCP2.2 issues.
It goes on to say that they have been in contact with the head of (Foxtel) engineering and it has been confirmed that there is a glitch in their firmware.

The email went on to say that there was expected to be a firmware update available in October 2018 or, this is no typo, March 2019. A discussion that I have since had with tech support, evidently Foxtel does ALL of its testing with the STB connected directly to the screen/TV. There is no testing done with an AV Receiver, much less a Matrix Switch, they don't know/care.

So, unfortunately it sounds like you guys in the US are suffering a similar problem, it probably is a engineering/firmware problem like we have here in Australia, the huge problem is likely to be getting them, Comcast, etc to acknowledge the problem and then to do something about it.

The short term solution offered by the distributors is either connect the box directly to the screen and use optical back to the receiver, obviously no good if there is a Matrix Switch involved, or to use a product like the Blustream HDCP11AB, I'm sure that you guys in the US will be able to source a similar problem.

Thanks for the info. Unfortunately these smaller x1 boxes are the smaller Pace boxes and only have hdmi out, no optical. I will definitely look into the issues that you’re talking about. Thanks again

I couldn’t find it but will call Comcast to see if I can find that section. Thanks

I will be taking a different monitor tv and check that next. I did check all of the ends and all look good and tight