I was doing a dub and it was working fine, then I added a couple of audio tracks as background music, I was able to get the sound lower than that of my voice

but for some reason, when I wanted a new track as my background music, I changed the volume so it could be lower but it doesn't work anymore, even when I put the volume to zero

and now this happens whenever I try to add a new track, I keep deleting the background music and putting something new in hopes that the volume settings will work but they don't, the track is louder than everything else

on top of that, the volume settings don't work on any of my voice overs either

prior to this, the original background music had dissapeared for some reason (before I wanted to put something else as the background music) I thought it was no big deal but now I wonder why, and it may have something to do with this new problem I have

is this a bug or did I do something wrong?