I've mentioned seeing Frankie Muniz backstage at several large Phoenix-area music festivals before. It appears the former Malcom in the Middle child star, and Scottsdale resident, is taking his interest in music to the next level by joining local rock band You Hang Up.
Muniz, who has stopped acting to pursue a racing career, no doubt helped by the fat royalty checks that'll roll in from the folks at Fox for a decade or so, will play drums for the band, which doesn't really seem to fit in to any genre beyond "radio-ready rock." You can hear seven songs on their MySpace, a site that I'm sure will get a lot more love now that Frankie is on board. Who knows if Frankie can actually play, but given his tendencies toward competition, I would guess he wouldn't try unless he was certain he would not embarrass himself.
By the way, this is definitely not a hoax since Frankie's girlfriend, who is sort of a celebrity on twitter, mentioned about it, as has the man himself.