HDR playback dimmer than expected

[qvattr0]

Describe the bug
During HDR playback, the player displays the video at a lower brightness compared to what the media file is supposed to output. However, hovering over the window while it's full-screen "flashes" the media with a higher brightness (brightness that I would expect if the player was not having any issues). The method I've been deploying for determining how an HDR file should look like is playing back the file on the Windows Media Player. That one never seems to have issues playing any of my HDR (except for DV) files. Another strange behavior I've noticed is that after playing around with making the player flash a higher-brightness HDR image while it is full-screen, reverting to a windowed mode caused my monitor to flash between HDR and SDR modes (or at least that's what it looked like based on the brightness shifts). The annoying thing is that when the player flashes the higher-brightness image, it looks almost exactly as the image shown by the Windows Media Player. I'll be including the contents of my mpv.conf file below:

### HDR Playback ###
ontop
volume=100
volume-max=100
fullscreen=yes
vo=gpu-next
gpu-api=d3d11
hwdec=nvdec-copy
gpu-context=d3d11
drm-vrr-enabled=no
video-sync=audio
spirv-compiler=auto
dolbyvision=yes
tone-mapping=auto
hdr-compute-peak=yes
target-colorspace-hint
tone-mapping-mode=auto
tone-mapping-param=auto
scale=ewa_lanczos
cscale=ewa_lanczos
dscale=ewa_lanczos
tscale=ewa_lanczos

I do not believe that the player is tone-mapping the video to SDR as the black-levels appear as what I'd expect them to look like in HDR. When I was initially setting up HDR playback and the player was not setup correctly, I was able to visually inspect a SDR tone-mapped image (from the same media file) with much worse black levels.

To Reproduce
Steps to reproduce the behavior:

1. Open Jellyfin Media Player along with Jellyfin MPV Shim
2. Turn on HDR mode in Windows
3. Proceed to play an HDR file
4. Notice that the brightness is not as high you expect, otherwise the image is displayed as expected
5. Move the mouse around and notice that the brightness occasionally increases and dims back down to the previous state
6. Exit full-screen and behold the screen start flashing between HDR and SDR mode for a little bit until it settles back to HDR brightness (the media playback still doesn't exhibit high enough brightness). Upon further inspection, I've realized that when the player is in windowed mode and the media is playing, Windows reverts to SDR across the whole desktop. Once playback is paused, the screen brightness returns to HDR (all regions except for the player).

Expected behavior
The image, in HDR, should look very similar if not the same as the one displayed in Windows Media Player. At the very least, the peak brightness should be similar.

Desktop:

• OS: Windows
• Version 11 2H22
• Jellyfin Server: 10.8.10
• Jellyfin Media Player: 1.9.1
• Jellyfin MPV Shim: 2.6.0
• Monitor: Samsung G8 OLED
• GPU: NVIDIA RTX 3080 Ti

Error Messages
None generated, as far as I can tell.