I have received a video showing the issue and with the help of the video, I can reproduce the problem on my end.
It is caused by the setting "Show lyrics on play". If you open the big player view manually by tapping on the song title in the mini player while playback is not running, it is always shown correctly. The problem also seems to happen with regular lyrics.
I have no idea about the cause of this issue yet, but now that I can reproduce it, I'm sure I can find a fix.
For now, please disable "Show lyrics on play". Open the lyrics view manually by tapping on the song title in the mini player and stay in the lyrics view during the gig. You can automatically show/hide the song list during playback so that you will still be able to select songs there.