Bug: Mute Clip behavior has changed in latest update
Before the current update, you could select several clips and Mute them, and each clip would flip its current Mute state. This behaved just like Clip Enable in Premiere, and it allowed you easily demo various takes with one keystroke. Now, if you select a mix of muted and unmuted clips, Mute sets them all to be muted, and pressing it again unmutes them all. Not the behavior we want.
Matt Stegner commented
This has not been changed as far as I am aware. What previous version of Audition showed this behavior?