Updating to Public Beta 2 was a little tricky... tried about 3 times, but each time on restart, the purple lines would show up and the installer would hang until it eventually rebooted into Public Beta 1. Finally turned off the machine with the case switch, rebooted and manually selected the installer from Clover... took a little while, but that did the trick. Updated to the latest WhateverGreen, Apple ALC, and Lilu kexts prior to the install, and deleted the -lilubetaall boot argument, and everything is working hunky dory. Sound, WiFi, Bluetooth, everything... AND Apple TV is working perfectly now. I think the whole problem was I hadn't authorized the computer (didn't realize I had to, was never prompted), but once I authorized the computer, even Apple TV started working perfectly.