Hi @maxmp there is this bug where the playing (image below) becomes stuck to the first ever song in the library and unresponsive to touch and it doesn't go to the now playing screen when touched it just gets stuck, it can be fixed when you close Poweramp from switcher.
it can be reproduced by launching PA from the widget.
Again, some desync between mini player and actual song loaded can happen during rescan, but it should normalize itself as soon as scan finished.
Desync happens due to the rapidly changing database, when some parts of PA may load different datasets, but this should be really rare case and only for the rescanning.
An alternative is to disable UI or parts of it during rescans.
If desync happens for you when no any active scan is happening (progress rotates in library header), please le me know.