Handshake for Player Led (LLDV) / (HDR) - Refresh Rate - need help :)

[Sebastiii]

Hello,
I'm testing A14 build compared to FireTV 4K stick through HDFury Vertex2.
I didn't have the same result, and I use Vertex2 for testing.

I'm in : Mode : ON

I have a EPSON 4k projector (no DV compatible) with a long handshake when changing resolution or HDR mode.
So when using FireTV (Kodi android) and have "Always HDR" set along with Vertex2 with custom LLDV, the only handshake switch is when changing refresh rate, all is working pretty good but didn't have FEL etc.

So I'm owner of AMB6+ that I just bought and trying to set up to reflect the same use.
And in fact, I didn't get the same video, darker on AMB6+.

Without Vertex2 in the chain, I only have Player LED (HDR) and with it, for ex some sample for testing DV didn't change like the "Eagle" one, image stay with no change in brightness, etc.
Also, the sample of Munsil with Horse, is too illuminated compared to FireTV.

So I did test the Vertex2 in the chain, and I was able to get Player LED (LLDV) and this time the "Eagle" sample, I can see image changing L1 and L1 + L2, etc.

So when looking at the wiki, the Player LED (HDR) should act like LLDV ? and with this setting, I don't need the Vertex2, so why I didn't have the same behavior ?

The second point and I don't know if it comes from A14 ou NG current build code.

But I have set to refresh rate change on start only on Kodi, like the FireTV, but on A14, the movie with the same rate 23.976, when starting some, the handshake of resolution (Hz) is trigger, so the delay is present where it should not change like, last DRR is 23.976Hz.

I understand that is the movie is 24Hz or 50 / 60 / 59 ... it should be change, but why when it's 23.976 to 23.976 ?

So I did try to set adjustrefreshrate override in advancedsettings.xml to force and tell 23.950 to 23.980 should be 23.976 with no luck :(

I have seen in logs :
2025-10-21 19:55:39.410 T:28444 info <general>: CRenderManager::UpdateResolution Before - Set fps [23.976025] width [3840] height [2160] stereomode empty [true] hdr type [hdr10] 2025-10-21 19:55:39.410 T:28444 info <general>: [WHITELIST] Searching the whitelist for: width: 3840, height: 2160, fps: 23.976, 3D: false:(0x4), stereo mode: 0 2025-10-21 19:55:39.410 T:28444 info <general>: Display resolution ADJUST : 3840x2160 @ 23.98 - Full Screen (16) (weight: 0.000) 2025-10-21 19:55:39.411 T:28444 info <general>: GLES: Maximum texture width: 8192 2025-10-21 19:55:39.411 T:28444 info <general>: CRenderManager::UpdateResolution After - Set fps [23.976025] width [3840] height [2160] stereomode empty [true] hdr type [hdr10]

<adjustrefreshrate> <override> <fps>23.976</fps> <refresh>23.976</refresh> </override> <override> <fps>23.975</fps> <refresh>23.976</refresh> </override> <override> <fps>23.977</fps> <refresh>23.976</refresh> </override> <override> <fps>23.978</fps> <refresh>23.976</refresh> </override> <override> <fps>23.98</fps> <refresh>23.976</refresh> </override> <override> <fpsmin>23.950</fpsmin> <fpsmax>23.986</fpsmax> <refreshmin>23.976</refreshmin> <refreshmax>23.976</refreshmax> </override> <fallback> <refresh>23.976</refresh> </fallback> </adjustrefreshrate>

Thanks for your help

[Sebastiii]

So finally, what I think the best from my POV is these settings :

DV Mode : ON
Player Led (HDR) because the projector is not DV, and it's without Vertex2
And set all to Tone mapping to SDR

With this, it does EOTP & Gamut to : SDR BT.709 and I find the video quality quite nice, deep black, good HDR, etc.

But, I have something that I would try to get ride, it's the blank issue screen when Ugoos apply something (surely DV to SDR map) on start and stop video (I didn't enable refresh rate changer for now when testing this mode).

So Is it possible to make the GUI already in DV/SDR Tone mapping to avoid such blank screen ?
On the Epson projector, the delay is quite long, 10 to 15 seconds.

If I disable hardware acceleration, I didn't have the blank screen delay, but it's slow and DV to SDR not working, but I mention it in case of !
Does apply a specific HDR InfoFrame with a payload can trick something ?

Thanks

[Sebastiii]

About the Refresh rate bug when trigger when it should not, it's fixed on CE-NO, at least it doesn't happen.
But no clue, if it's on Kodi / Linux kernel or CE code, but it's fixed !

For the one when DV is trigger, it seems to be related to Dovi.ko code / amlogic hardware, so I fear, there is no hope for this one !

[Sebastiii]

What would be really nice, is to have some options to force GUI, in some mode as fixed, to avoid handshake negotiation like does FireTV !
I have noticed that for ex mapping to SDR, but it can also to DV, A14 send a signal format change to SDR instead of HDR (on the Epson, it triggers the delay :( on start and on stop).
When a video is running, and I select VS SDR, on stop, the GUI stay in this mode, so I think it's possible somehow to be able to set a forced GUI mode.

[tjayz]

I had identical problem with long failed handshakes. Solved it by reverting most settings back to where they started here and disabling all add-ons not required to run the skin. Do not need to reinstall from scratch just copy the settings.

https://www.youtube.com/watch?v=kviwN0KKRgQ
https://justpaste.it/f1zpd

After verifying issue gone, slowly reenable add-ons and essential settings in controlled groups. I never reverted all and never managed to isolate root cause of the handshake issue but everything works as intended now. None of the settings that I thought were the cause mattered at all and downgrading A14 current build to A14 release, A13, A12, or A11 had any impact nor did any advanced setting for any release.

[Sebastiii]

I didn't have any addon, and it's not a delay related to wrong handshake, finally.
My projector is long on this, but I have the same delay on Windows when changing resolution.

I have done more test and now, if I disable RRC (Refresh Rate Changer) all is working correctly, except that the video didn't match if it's a different video FPS.

When enable RRC, it seems that DV or HDR or something like that didn't get the proper FPS and lead to trigger RRC when it should not, because different type of video have the same FPS.

So I'm trying to figure out how to compile code by adding logs to try to understand where it lies, but I didn't succeed to apply patch.
I mean, I build the source and if I change something on a file and build again, it keeps the previous change aka, it builds without my new change.

Must be cache files somewhere.

Anyway thank you to have taken the time to answer me 👍

[tjayz]

Forgive me for not providing enough detail but, the problem I was having was after video started within 15 seconds screen would go black and cycle repeat in endless loop, the handshake was not bad it just was not allowed to ever complete and keep starting from scratch again and again. AVR would show video and audio settings of the content and revert back to the settings it displayed while nothing was playing then cycle back to the content settings again in endless loop and screen would go from black screen back to video from the content. The only setting which had an impact was system>display>delay after change of refresh rate. By setting it to a high value you extended the time it took proportionally for the cycle to begin, and like you I was 100% convinced it was linked to the refresh rate change being triggered since the content played fine until that trigger. Reverting my settings back to what they were based on the install guides I showed you fixed it for me, when no settings that I intentionally tweaked prior to that which were refresh rate related had any affect whatsoever. Some other setting I had somehow indirectly affects refresh rate change for some reason...

[Sebastiii]

Ok I see, effectively, it's different because it cycles but in final related to trigger at the wrong time.
Thanks for updating your explanation 💪

[tjayz]

This problem came back for me and figured out why and wanted to provide solution. My TV is LG oled and aspect ratio settings must be set to 16:9, just scan to on. If you allow these to auto it will work for a long period of time until you start playing a lot of highbitrate, .iso files. These files make the handshake take longer, longer delay till video displays, and somehow permanently corrupt the auto aspect ratio settings during the handshake over time till it eventually becomes a death loop handshake. That death loop will affect any file, any audio or resolltion it seems. Possible the JD-Bluray app might be involved not sure. But setting correct aspect ratio settings manually fixes the problem on these kinds of tvs which may help others.

In your case, using a projector, I am unfamiliar with what settings you have access to which allow you to control aspect ratio manually, but I would give it a shot, or any other auto setting, to reduce the overhead performed during the handshake in the first 7 seconds or so.

[Sebastiii]

Thanks, with avdvplus build it works better, but I'm trying to avoid a max of refresh rate change, only the one needed for now, it works better on my side, but I keep, your finding, I can't fix a specific resolution on ma Epson, I can only on CE build, but on the AVR, we can force it (default one), so I need to try, but it override when forcing on the playing device :)