I've got one that I love (7-100), after seeing Frank Zappa play thru one in a clip on youtube, it was a no brainer . Got a question though, mine seems to have a buzzing sound after each note, doesn't sound like a mechanical rattling or anything, more like an electrical buzzing, as the note decays. anyone else have this? is there a fix? Its a new one btw, not a 70's model.