I have now installed the latest nightly on v13 Piers 21082026 on my n100. HDR now works without stutter (as it did on the last v12 nightly) - so that issue is thankfully resolved. However, the problems still remain regarding sound drop outs or black screen but only when starting or stopping HDR.
So, for example, if I play an HDR file, either the screen will go black with no sound, and the only way to get the picture back is to stop the file playing using the remote, or the file plays perfectly and when stopping playback there is then no sound on the GUI. Only way to get the sound back is to use the sky42 script. Once the screen has gone blank - you cannot see the OSD, so you have to remember the remote actions.
Sometimes though, even when booting up from scratch, the screen remains blank - the sky42 script can bring the picture back, but not always, then it is a case of rsh to reboot. I have upgraded from v12 (which I manually installed), and therefore I have not wiped the n100 and started again, but that would take a long time and hopefully not be necessary. New 4k certified HDMI cable. No audio drop outs when playing, only on stopping playback. However it is possible to resolve the audio (if that is all that has gone wrong), by playing a file with multiple audio language and switch language, then it works again. If the screen has gone blank after stopping a file, you can only bring it back by the script or a reboot. Even the reboot may need the script.
Any thoughts. Happy to share logs or anything to help investigation. Just let me know what I need to do or any further info required.