Hi there, I hit this pesky issue of the Thunderbolt Firmware Update 1.2 that keeps showing up in the App Store in Mavericks. I read a bit about possible causes, and Apple's KB advises to disconnect Thunderbolt peripherals before attempting the update. But I have none. Discussions say to attempt this only with AC adapter connected: I did, every time, but it shows up repeatedly nevertheless. Then as a last-resort, many relied on reinstalling their OS. I did, too, erasing the HDD and downloading a fresh copy overnight using the recovery boot. And the update keeps popping up! In case this is relevant, the chip marked Parade PS8301, apparently an HDMI shifter, stays hot even when the computer is sleeping. If that's helpful to the matter, projection a HDMI TV doesn't work at all: TV displays "no signal". PRAM reset didn't change anything. Servicing at the Genius Bar is not an option as this machine just fell out of warranty. Any idea what's going on in this machine?