Issue - Part of Rekordbox-screen messed up (screenshots)

Windows 11, Pioneer DDJ-800, Rekordbox 6.6.1 (note: issue already occured in version 6.6.0)

Please see below screenshots, taken at different days, I think the first 4 screenshots are from using 6.6.0 and the last one from using 6.6.1.

This issue occurs randomly and persists until I minimize and then maximize again the Rekordbox-window.

What's going on and how can I fix this?