you weren't banned for the music in the background (although that is what I initially warned/muted/kicked you for), you were banned for arguing with not only me, but multiple other staff members as well. when they told you the same thing I did you told them the same thing - "you can't punish me for having music on in the background!" if you read the ban on SourceBans, it doesn't say "playing music in the background," it says "arguing, ignoring admins" which was why I banned you
keep in mind this music wasn't 'quiet' or 'faint', it was loud enough to the point where a) I could tell it was Enter Sandman by Metallica and b) it was hard to understand you. that is why I asked you to turn it off; if someone has a bad microphone or something in the background that can make it difficult to understand them (read: music) then staff members are by all means allowed to ask them to either fix it or to stop using their mic (unless this has changed since I was an admin, but it hasn't to my knowledge)
it's a 24 hour ban, wait it out.