[DaveBlake]

I know partial logs are a frustration, but this really does have the essentails in it. Hope it reveals something useful?

Yes, it is something unexpected so probably is useful. I'd need a fuller log with "Video" enabled in the component specific debugging to understand more.
At least that message is something to search for in future logs.

Do you feel this issue happens with certain files and not with others?
If so, then getting a sample file to me would be useful. If I can reproduce the issue, then fixing it becomes a lot more likely.

In pursuit of video stutter (on LE 7.90.007) - pictures freezes then catches up with the sound that continues.

As before Adjust display refresh rate to match is enabled
Did not have PLL adjust enabled as you thought, but tried setting it to max. This was horrible, so set it back to off.
Enabled sync playback to display.

Played several videos and did not get any noticeable stutter. The log is huge as have video debug enabled, but does not contain any interesting

Code:

ERROR: CMMALVideo::GetPicture - called but m_output_ready is empty

messages. But does have a lots of CDVDPlayerAudio::SyncStream calls. Not sure if that is because the setting change avoided the issue, was playing different files, or the logging level change.

So more testing needed to confirm, which I will do later, but it would seem that enabling sync playback to display solved the stutter.

The question I am left with is how is a user meant to know what video settings to use? Previous Kodi versions simply ran out the box for me, and without your suggestions there is no way I would know to change any of these settings or what they do.