SDR to HDR breaks after playing a Dolby Vision file


I am using CoreELEC on the Homatics Box R 4K Plus from a USB flash drive, and am having an issue. I have “Tone Map SDR to HDR” turned on in Settings > System > CoreELEC, and for the most part, it works well – the Kodi UI is tone mapped properly, SDR content is tone mapped properly, and HDR10 content plays normally. However, when I play a Dolby Vision file, the file plays correctly, but upon returning to the Kodi interface, my TV has returned to SDR mode, and the colors are all warped. A reboot returns Kodi to normal.

In other words, the “Tone Map SDR to HDR” feature stops working after playing a Dolby Vision file, and CoreELEC outputs a (broken) SDR signal until a reboot. I searched the forum and saw one other user with this issue but no solution mentioned.

I have re-tested the latest nightly (CoreELEC-Amlogic-ne.aarch64-21.0-Omega_nightly_20240420-Generic) with a different USB drive and the issue persists. A log is available here:

Any ideas? Could this be a bug or do I have something set incorrectly?