How to remove your BandMix account
From their FAQ: You can remove your listing by logging into your account, clicking on Account Options and then on Decline Service. This will remove your entire profile.
Posts on the BandMix Forum cannot be removed by users, but you can contact the site’s staff to have them removed (be sure to include the URLs to the posts in question).
Helpful Trick: Removing online data
Helpful Trick: Remove third-party logins
If you signed up for BandMix using a third-party login such as Facebook or Twitter, you probably want to revoke all access from BandMix. Click here to find out how.