As one who's always trying to figure out IF something can be done, I was thinking today..
What we don't have yet is an app or something that enables use of a CB radio.. Since I do ALOT of motoring, in the past I've always kept a CB in my truck to 'watch' for smokies and problems on the road.
The big downer for me was I couldn't listen to the music AND the CB at the same time..
So, I figure (while I haven't looked) there are probably some radios out there that can be controlled with a serial port.
Add that to the fact that the Empeg has AUX in, and voila! an app:
Application runs in the background on the empeg, and 'listens' to the Aux port. When the CB's squeltch lets a signal thru, the program auto-switches from the player to the Aux-In, until the squeltch goes away, then resumes the player. (Could take that one step further, with some type of serial connection, do scanning, looking for good channels..)

Remember, I'm not asking is it's PRACTICAL, just DOable.

The only I'm-Not-Sure-About points would be the 'listening' to the Aux port while the player is running. Is that even possible? (Accessing a different audio channel not selected.)

Am I insane? Did I pick something that is practically impossible?

Me, conjouring up different ways to just USE my Empeg.

What about just mixing the input all the time... with the audio overlay patch (IIRC, it's in hijack now), you can have two audio sources playing smoothly together. I have no idea if that includes the aux in, it may not.

Then you'd be listening to both all the time. Just pause the player and your CB is all you hear. Would that be close to what you had in mind?

How's about using the extmute_on and extmute_off hijack functions? They let you inject button codes when the mute line goes high or low.

If you can get access to a squelch on/off signal in your CB and produce a 0/12V signal from that, you're home 'n hosed without programming anything apart from the config.ini file.