...SacsTC has been doing another project in the rig.

He wanted to shut off the 12V power to the coach so he turned off
both the chassis and the coach battery main disconnect switches. (These are the switches that are located in the battery bay

.) Imagine his surprise when he gets back inside the coach and the radio is still on.

He did turn it off by shutting off the "salesman switch" located by the front door.
Are any of you good at that math stuff

...you know
..."if a=b and b=c...then "a must also = c" ...in other words..

.This means your radio is still drawing power for all of you who have bypassed that switch!
(and possibly other things that draw power through that solenoid.
)
..then again

...maybe it is just our coach and no one else has this situation.

It could be something else to check out if your batteries keep going dead.