Since the October update resulted in no 4k playback for me, I reverted back to the old kernel (hotfix), where playback works fine.
So now I’ve tried the latest kernel from devel:
3.14.29-127-osmc #1 SMP Sat Nov 10 20:21:10 UTC 2018
but unfortunately 4K playback still doesn’t work for me.
Log: http://paste.osmc.tv/isafoveced
Sometimes I get only black screen (No input signal), sometimes it plays fragments of sound and shows a stuttering picture for a fraction before going to black/no signal again (as in this log).
Hope it works, and happy to test new kernels again (instead of going back to august)…