[Milhouse]

Okay, thanks for that. I went back to 0819 and it was okay, no constant frame skipping on 720p. I worked my way forward and 0820 and 0821 are fine, 0822b skips frames constantly and loses audio sync. 0823 did the same thing, so it looks like something in 0822b broke for MMAL, 720p live TV and recordings.

Setup is Mythbuntu back end, HDHomerun for TV tuning, RPi2 front end
OMXPLayer unchecked
MMAL checked
Adjust refresh rate unchecked
Resample Audio

Thanks, that information will hopefully prove useful.

Is there anything else that I can supply that might help?

Only the usual if you haven't provided them already - a debug log (wiki) and ideally a small sample file with which to reproduce the issue (apologies if you've provided these already - keeping track isn't easy!)