Last.fm is adding songs from someone else to my profile.

I love Last.fm and I think you provide a brilliant service.

Unfortunately, someone else's tracks have been appearing in my profile lately. This has been going on for at least three weeks. This is not a random selection of music, it appears to be reflecting an actual person's listening habits (i.e., one band's music or style of music will tend to appear together, it seems to be a coherent taste in music, etc.)

I don't think my account has been cracked, because I've changed my password and it's still happening. (Also, I think if someone cracked my password as a prank they'd be putting up embarrassing tracks, but the tracks are nothing notable.)

I know it's not someone else on my laptop, because nobody else uses it, and most of the songs don't exist on my laptop.

I contacted you after reading the following, but never heard back:
http://www.last.fm/forum/21713/_/3667...

Please help... I don't want my Last.fm profile to continue to be corrupted/diluted.

Thanks!