What about hooking the Brake Pedal to the Mute Button?
Yeah you'd need a relay or something.
But if you get a dangerous blip the first thing you do it tap the brake pedal to cancel cruise.
If you don't want to tap it, don't.
If you're leaning on the brake you're already slowing down.
If you're stopped at light you're already Muted !!
It's not perfect but it almost works.