MuseScore4: Playback at different tempo faulty

I use MuseScore to play single part Irish tunes I've created. These were created in MuseScore3 and has been very useful for slowing tunes down to practice with until I can get up to speed.

MuseScore4 does not handle tempo changes well at all. The MuseScore3 files work great at 100% tempo at whatever the tempo of the piece is set at. But if you change the tempo it will play 4-8 bars and then seems to play from the beginning as a second part while continuing on with the original part. Then after a few bars it stops and goes back to normal.

Irish tunes make frequent use of repeats, playing each part twice, with two or 3 parts. When playing that same tune at a different tempo and letting it go, when it gets to the second part the bar that shows what is being played jumps ahead and is moving along in the wrong position and when that bar reaches the repeat the bar jumps back to the matching repeat even though the notes played haven't gotten that far yet, and the notes played start at where the bar is.

This happens the same with the 6 or so of my fMuseScore3 files that I have tried changing playback tempo on. I included one as an example.