You may need to put a ampere meter between the negative ground cable and the battery to check for any draw. You can use a test light too. If the light lights or the meter shows a draw then try disconnecting the alternator cable on the back of side.

You may have a leaky diode to ground. It can be a slow drain sometimes when off. The charge current will be lower in relation to voltage when running. The conversion from AC to DC current will be going to ground thus causing the regulator to raise up as it was a load. It should show the ideal 13.6 to the 14.2 and about 15 amps going to the battery by itself, despite the load.

The next best is removing fuses one by one to find the bad circuit. I mentioned this second because the alternator doesn't go through the fuse panel. Plus, I like working while standing up as much as possible.

Since you were working/playing around with the console. I suspect it could be the cigarette lighter outlet or the wires to it, touching on the back side. I'll stay with you on any other loose wires under there too!

It is hard for me to believe that a radio can run down the battery all by its lonesome. Then again that juice is going somewhere!

Phil