There's a setting in the Uconnect 5.0 that supposed to let you choose if you want the radio to default off, or if you want it default on and playing the last thing you had playing. No fiddling with this seems to make a difference....AC/DC weather you want it or not.
Another niggle: often times I have to jump in and back up a loading ramp. When the PM is in reverse, the backup camera is on, and while the camera is on the radio controls are blocked out. Volume included. So I jump in, start it, put it in reverse, and then I get AC/DC at full blast and there's nothing I can do short of putting it in drive to turn it down. Meanwhile, the dock guys are looking at me like I'm an idiot having a rock moment while I'm backing up. Maddening.
Perhaps the solution is to create an MP3 named AAfirst, and have it be either just dead air, or maybe it be the sound of a truck backing up.