Has anyone ever gotten in trouble for uploading to Grooveshark or SoundCloud?

So, Grooveshark and SoundCloud quite rightly require users to have the rights to the tracks they upload, but does anyone know of instances where users got into legal trouble when they (inadvertently) uploaded material copyrighted by somebody else? Both sites take down copyrighted material when the real owner asks, but the only actual penalty I've seen for the uploader is that on SoundCloud they may be prevented from uploading anything thereafter.

Grooveshark has of course been sued repeatedly for hosting copyrighted material, the general argument being that when they take a track down at the copyright-holder's request the same track gets uploaded again more or less immediately. I'm not aware of suits against SoundCloud, but they're in pretty much the same boat and doing their best to stay out of trouble.

The question is, has the RIAA or anybody come after any users of those services because of what they have uploaded? Has anybody gotten into any trouble beyond losing their account or just their uploading privileges?