Rekordbox deletes entries | output mixer miserable

1. miserable sound quality from the speaker:
I recently purchased Pioneer DJ DDJ-FLX4 and connected that to my JBL Partybox 110 via TNP 6.3 mm jack to RCA cable, RCA audio cable. This worked wonderfully until yesterday. Since yesterday, the sound that comes out of the box is miserable and partially muted or without bass. I have not made any changes to the setting other than installing the update from Rekordbox yesterday. Could it have something to do with that or maybe the mixer is a montage model?

2. Rekordbox deletes entries:
It has happened 2x now that I have had to re-label most of my library with my comments and disc number. This has happened once after the update as well as after a restart. What settings do I need to change for this to be saved? Oddly enough, for some titles, the entries remain. Or is that also related to the update? I have little desire to label the titles again and it is then deleted again. Specifically, it is about the columns "Comments" and "Disc no."