14.0.4 performance

I just finished my usual video edit on 14.0.4 and it is slower than 13.  Thumbnails take longer to appear, scrubbing is nasty but the biggest problem is dropping frames.

H.264 that plays fine in 13 stutters terribly in this version.  Yay progress!  

I edit at least every week - and always the same project, same file types shot on the same camera (and yes I did start with a new project, and imported the old). 

I'm trying to think what was added in 14 that I couldn't live without, and I'm struggling to think of much.  Seeing as I'll be stuck at home for the next month or 2, this is probably that point I've been waiting for to learn resolve.