Am I misunderstanding Adjust Refresh Rate on Start/Stop?

I am testing out a new HDMI 8x8 Matrix Switcher to replace my existing Key Digital CSK. For the Vero, it is plugged into one of the Inputs on the switcher and there are 4 TVs in the house that plug into the outputs.

I have OSMC set to do the Adjust refresh rate on Start/Stop so I can get 4k to output 4k and 1080p to output 1080p. The new switch works fine with 4k and the GUI at 1080@60. But when outputting 1080@24hz, the TV says it cannot read the signal.

With the old switch, everything seems to work. If I play a 4k iso, my TV (Sony XBR for testing) will say it is receiving a 4K single. If I play a 1080 movie it will say “1080/24Hz” or whatever is appropriate.

I just got off the phone with the Tech support of the new switcher. I am not sure I agree with what the guy’s explanation of the problem but wasnt about to argue being he works in the AV industry and I dont.

I am saying it shouldnt be a problem, the receiving device should just renegotiate the handshake. He is saying that having the EDID dynamically adjusting like that is “never good”. I think the real answer is they dont want to deal with that scenario. Fine.

So, to my actual question. I explained that if I force OSMC to output at 4k for everything then the 1080p sources will get upscaled at the device. The same would go for, say, a Roku or AppleTV. He said that the EDID is just a string/name that is sent as part of the handshake. So, even if my TV says “4k” in its info display it is still receiving a native 1080p single and there would be no difference in what the picture would look like. Is that right? I always assumed that if the TV says “4k” it is because it is receiving a “true” 4k single from the source.

Content that has been recorded or encoded at 1080 will only display at 1080 even if you send it to an 8k capable display. Your display may upscale the input to fill the screen but the quality will never increase above 1080p. You must have content recorded/encoded at a 4k resolution to view that content with the increased quality that 4k provides.


If you don’t get this with Vero connected direct to the TV or through your old switch then there must be something wrong with the new switch.

@ActionA Yep, I get that. Nothing can magically create pixels there were never there in the first place to make an HD picture true 4k quality. But, the TV/display is fixed pixel. So SOMETHING has to generate those pixel to fill the screen - hence the upscale. And my assumption was that if the TV says it is showing “4K” it is because it is receiving a 4K signal that was upscaled at the source (assuming it is encoded in HD). So it is actually getting 8 million pixels (3840 x 2160) over the wire generated by the source (Vero in this case).

@grahamh That was my conclusion but wanted to get other peoples opinion because I was surprised by his statement. Matrix switches are very complicated so I would assume that their tech support would be pretty knowledgeable. My original switch was about $3k new. This one is $1k new. Guess that’s the difference…

What should be happening is when you connect a display to a source it sends an EDID and the source must send only signals that the display can handle. Quite how it works if you have one source and multiple displays connected at the same time, I’ve no idea. But logically, you should only be able to send a signal they can all handle.

You can check what capabilities Vero thinks the display(s) have with:

cat /sys/class/amhdmitx/amhdmitx0/edid and
cat /sys/class/amhdmitx/amhdmitx0/disp_cap

Thanks @grahamh. In my test everything was 1:1 between source and TV via the switch. In other words, I have the vero set as the input and only ONE TV set as the output - the Sony - just to make it as simple as possible.

I might try those commands before shipping it back just to see.

For that, you can get 3 more Veros :wink:

Ya, I know. Its just so convenient only needing one of each device and putting them all together in the closet. I wish I could find a cheaper hobby :open_mouth:.

Seriously, let each TV have it’s own Vero and setup a NAS.
With that setup each TV could be waatching unique content too.
The Vero fits nicely behind a TV too since it’s so small.

I have a NAS actually. :slight_smile: But I also have 2 Verizon Fios boxes, an Nvidia Shield, Vero, Roku Ultra, and a chromecast (which is now kind of redundant at this point). And I am sure I will add more in the future. All go through the switch and any can be watched in any room. It is rare there is a conflict with so many choices.

Its the convenience I am paying for with the switch…

Do you have 1080p/24 selected in your whitelist? If your UI resolution is set to 1080p/60 but you only have have 4k/24 in your whitelist (or perhaps no whitelist selections at all, not sure about that) then Kodi will likely upscale to get to a preferred frame rate. I’m pretty sure the current version of kodi prioritizes matching frame rate over matching resolution.

@darwindesign That is an interesting point. I have never actually touched the whitelist settings. So it seems that when I play something it either outputs as 4K or 1080p. So, if the movie is in 480 or 780, it outputs automatically to 1080. Might play with it some more although I doubt it would help with the problem with the switch unfortunately.