Hey there, so I managed to solve this with help from HEOS support.
The issue was the latest version of the firmware was not working correctly if updated from the factory settings (new shipped device from Amazon).
It only works properly if upgraded from the PREVIOUS version of the firmware.
The solution is really straight forward, and worked for me. Contact HEOS support directly, and ask for the file for the previous Firmware, so you can THEN do the update to the new one.
I do know that HEOS technicians are right now creating a fix for this, so it could be that they have already solved it, and you just need to reset to factory settings again, and do a new update. But speak to them first.
I found them very helpful and it didn't take long to fix.
Good luck!
Mark