I’m running a RPi with osmc . My TV has no HDMI but VGA. I use a cheapsky HDMI to VGA Adapter. With all RPi options like hard coded mode and HDMI hotplug off.
It works like a charm when I start the RPi with the TV turned on or replug HDMI with the TV on.
However if I turn off the TV and back on I only get a black screen.
Any ideas?
I just had to try this. I also get a black screen but it comes back as soon as I hit the button on the tv remote to select input (10-year-old Panasonic).
Have you figured out how to get 1360x768 out of the adapter?
Nope, I hear the UI sounds but the screen doesnt come back up.
@1366x768 DMT mode 81?
I guess your answer is yes, then. 
I think this must be adapter/TV sensitive. I doubt much can be done from Pi/Kodi. For the record, my adapter is Ugreen.