slightly

ok so here's my problem, i cannot stop biting my nails, it keeps me from playing bass because they hurt so bad sometimes. Can anyone help me here? PLEASE!!!

My volume knob is slightly moving. How can I secure it? I removed the cover from the back but I don't see it being attached with any screws which I can tighten.

I recently got a used fretless corvette std 5 from a talkbass member. Overall, the bass is in good shape. The fretboard is slightly worn from the initial owner using roundwound strings. I cannot seem to get it to show up on the pictures. Should anything be done about the fretboard to prevent...