Running 10.10.2 on MacBook Pro (Retina, Mid 2012) with 2 Apple Thunderbolt Displays: no sound on the Cinema Display, no brightness control in pref. pane.
How to I get sound and brightness as before the 10.10 upgrade?
KJ
MacBook Pro with Retina display, OS X Yosemite (10.10.2)
Is the USB cable connected to the MPBr?
There is no USB, it's Thunderbolt. Prior to OS upgrade, it worked, and not it does not.
K
There is no speaker on the older ACD units, but if you have a newer model, with a glass front, then speakers are present. You need to ensure the USB cable from the ACD is plugged into your Mac, otherwise sound and other features will not work. I think you have misunderstood my previous answer. I am fully aware the ACD connects for video via ThunderBolt, but also have other cables coming out of it, to activate the USB ports on its rear.
cinema display Yosemite volume brightness
