Ben Sones writes, "This post is a public service announcement. Last night, my Strat developed the dreaded "down strum has stopped registering intermittently" problem that so many people seem to be having. Sometimes it worked fine, but other times (especially in fast-strumming rhythm sections) it would either not register some of the time, or double-strum. Up strum (the real down strum, for actual guitar players) still worked fine. It was bad enough that I was failing out of songs on which I can normally get four or five stars.
I read all the official forum posts in the RB tech forum (which propose a number of different remedies), and then decided to open up the case and have a look at the mechanism for myself. Unlike the GHIII guitar, you can open the back of the Strat without voiding your warranty (the Les Paul has a sticker over one of the screw holes that voids the warranty if you break it). So before RMAing it, why not have a look?"