Can't change hdr-reference-white on the fly anymore

mpv Information

mpv v0.41.0-674-g8fc1a10a4 Copyright © 2000-2026 mpv/MPlayer/mplayer2 projects
 built on May 19 2026 00:19:27
libplacebo version: v7.364.0 (v7.360.0-48-gc67c2cb-dirty)
FFmpeg version: N-124539-g7ac3d83e7
FFmpeg library versions:
   libavcodec      62.33.100
   libavdevice     62.4.100
   libavfilter     11.17.100
   libavformat     62.17.100
   libavutil       60.31.100
   libswresample   6.4.100
   libswscale      9.7.100

Other Information

- Windows version: Microsoft Windows 11 [Version 10.0.26220.8370]
- GPU model, driver and version: Intel(R) Arc(TM) Graphics 32.0.101.8724
- Source of mpv: shinchiro [https://github.com/shinchiro/mpv-winbuild-cmake/releases/tag/20260519]
- Latest known working version: Zhongfly (because shinchiro couldn't be updated for a month) [https://github.com/zhongfly/mpv-winbuild/releases/tag/2026-05-01-48bd97b5bb]
- Issue started after the following happened: Updated to Zhongfly (because shinchiro couldn't be updated for a month) [https://github.com/zhongfly/mpv-winbuild/releases/tag/2026-05-01-5e847889b3] and then suddenly, I can't change hdr-reference-white on the fly (console/profile keybinds), but still be able to if configured in mpv.conf before launching it.

Reproduction Steps

1. Turn Windows HDR mode on
2. Open mpv.exe
3. Open console (`)
4. Type set hdr-reference-white 616 and press enter

Expected Behavior

The brightness limit should be set to 616 nits or whatever that means.

Actual Behavior

The brightness limit doesn't change.

Log File

output.txt

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested and confirmed that the issue exists with the latest release version or newer.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

Reproduce the issue on Windows with HDR enabled using the console command set hdr-reference-white 616, then inspect output.txt while comparing runtime changes with the same setting in mpv.conf. Done means changing the value through the console or a keybind visibly changes the brightness limit without restarting mpv.