4k videos no source and weird resolutions

So I got my Vero4k up and running, have it at 1080p60, all looks, goods GUI is bright and crisp.

Playing 4k HDR videos and they played but then realized they where @ 1080p60 as reported by TV, switched GUI to 4k24 and all good, videos reported by TV at 4k24 HDR UHD but GUI was very laggy, dug about and worked out GUI should be 1080p60 with auto adjust refresh rate so changed, success sort of…

4k24 HDR videos sometimes play and sometimes crap out at the start whereby I can here broken sound through the Yamaha AVR Amp but no picture, amp then usually says no decoder as in it’s receiveing nothing and TV usually complains of no source, I stop and try again till it works and then it reports 4k24 HDR UHD etc and the GUI during play fits the screen.

Also normal 1080p videos in 16:9 I noticed report as 1080p24 but the GUI during play is off the edge of screen top and bottom. Couldn’t work out a way to fix this until I went back to main Kodi GUI, switched to 1080p24, calibrated the screen then put it back to 1080p60 and now playing 1080p24 it fits the screen properly but isn’t this a compromise somewhere?

Anything I need to fix and is it possible to play everything but 4k24 @ 60 and let 4k24 play @ 24?

Vero4k to Yamaha amp (not that old) then to Samsung TV (not that old), which can play every format currently out etc. according to specs. also cabling is the higher throughput 4k stuff and I kind of prove it works as if I put the GUI into 4k it plays it fine every time as 24 HDR UHD.

Set the GUI back to 1080p60.
Enable Adjust Refresh Rate and OSMC will automatically switch to 4K when necessary.

Sam

Yeah that’s what I said I’ve done but…

Unfortunately it doesn’t then play 4k sometimes giving me no source at TV and sound at amp stuttering before dieing till I then choose stop and try again with my fingers crossed.

Also 1080p24 isn’t scaled to screen correctly and too big, I can calibrate it in GUI whilst at that resolution but somehow think this might be a compromise in quality of picture.

Check your TV for a setting called “Just Scan” or “1:1”

Found an option in the end called “Fit to screen”, this sounds like a horrible option that you need off or it’ll mess with the picture but in my testing from the tivo and kodi seems having it ‘on’ doesn’t mess with the picture.

With it on and calibration reset it all fits the screen properly in 4k, 1080p at various refresh rates etc.

The only problem I have now is it having 4k being a hit and miss if it works first time or needs a few goes to play, any ideas?

I see exactly the same issues with my 4K HDR capable Yamaha Soundbar.
A Firmware update supposedly added support for 4K HDR, but that may have only been 4:2:2 10bit and not 4:4:4 10bit that OSMC is using.

This looks like a Yamaha issue, I’m about to Email them and see what is going on and what Chroma input/output they actually support.

In reality we really need a working 4:2:2 Chroma mode.

On the specs of my amp it says “4K60p 4:4:4 Pass through, HDMI (6 in/1 out) with HDCP2.2 (3 in/1 out), 3D and Audio Return Channel”

Having poked about there’s an option to force my amp into a lower spec mode, not sure if it’ll fix it as at work but what are the implications of forcing it down to 4:2:0? This Chroma Subsampling: 4:4:4 vs 4:2:2 vs 4:2:0 - RTINGS.com article suggests not a lot for movies but true?
Don’t see the point of of having all singing all dancing 4k vids to then stunt it a bit.

Obviously it can and does work just not all the time, I might poke about the amp info whilst it’s playing a vid to see what it went to, I think it can show this info.

For reference my amp manual is here Configuring The System Settings (Advanced Setup Menu); Advanced Setup Menu Items; Changing The Speaker Impedance Setting (Sp Imp.); Selecting The Remote Control Id (Remote Id) - Yamaha RX-V779 Owner's Manual [Page 120] | ManualsLib

Advanced settings > “4k Mode” > Mode 2

This article http://www.acousticfrontiers.com/uhd-101-v2/ further expands on the fact 4:2:0 is only supported @ 50 or 60fps is here we may have a problem.

Would a 4k24 movie look weird @ 4k60 display?
Currently hypothetical until I can play with my hardware.

You shouldn’t be playing at a non native refresh rate if possible.
I’d be surprised if Yamaha don’t support 444,10-bit output. I’d appreciate it if you guys can keep me posted with your findings.

Sam

Well so far the few 4k movies I have and watched have all worked first time.
Maybe it’s not an issue maybe I’ve just got lucky so far.

For now I’ve not engaged the ‘Mode 2’ function.