DV issue with Asus PG27UCDM, won't "stay" in DV mode

[swinokur]

Hi there,

I've been playing with CoreElec for about a week, so I'm pretty new at this! There's a pretty good chance this is pilot error!

But, I have here an AM6B+, and an ASUS PG27UCDM monitor.

The monitor doesn't support "TV LED" or "DV-STD" (as far as I can tell from looking at the edid.) asus.zip Which I've attached here in case you want to peek at it.

I've been trying to use the "Player LED (DV-LL)" mode such that the asus stays in "dolby vision" mode pretty much all of the time. But this doesn't seem to be happening.

• When I play a .mkv that is dolby vision the monitor does go into the mode and shows the top right corner icon.

• When I play a .mkv that is HDR, the player looks like it is sending through the VS10 engine - but the screen tells me that it isn't even in HDR mode, it is SDR mode and the image is faded looking. (at least it isn't purple and green!)

• the only way I can keep the monitor in any HDR mode "all the time" is if I put it into dolby vision -> HDR mode, then everything is processed and sent out via HDR10.

• It sure seems like there's "something extra" needed to tell the monitor to go into DV (and stay there?)

I have tried all the various settings I can possibly think of without any real success.

I have tried three of the CPM builds, none of which make any difference:
CoreELEC-Amlogic-ng.arm-21.2-Omega_20250302082815.A14
CoreELEC-Amlogic-ng.arm-21.1.1-Omega_20241123122951.A11
and
CoreELEC-Amlogic-ng.arm-21.2-Omega_devel_20250820105844

I've updated the firmware on the monitor to the latest as well, with no change.

Has anyone else had any experience with this monitor? Am I just exceeding its capacities?

Any other tips/tricks/diagnostics I should run, please let me know.

Thanks!

[swinokur]

just to follow up in case anyone else see this - I verified today with a LG CX oled (so its an older screen, yeah) - that the CPM build CoreELEC-Amlogic-ng.arm-21.2-Omega_20250302082815.A14 works exactly as I would expect it to work with a "proper" screen. TV-LED / DV-STD Dolby vision pops right up, screen stays in Dolby Vision, etc.

So I guess this screen is going back to the store. I guess I'll have to wait and see if anyone releases a 27" OLED screen that actually supports TV-LED/DV-STD Dolby Vision...