I wonder if the last owner put an old radio in the jeep just before they sold it.
First thing to do if you haven't is to reboot the radio using the main fuse. Might temp fix the issue.
I have a feeling the radio needs to be replaced, or the wiring needs to be redone. Redoing the wiring is obviously cheaper and may fix your problem, but by no means is that guaranteed.
I would also check the fuses and make sure they are the correct size. Won't fix the current problem but if they have too large of fuse in a spot you can avoid future ones and track down a fault they cheated to fix. Bigger fuse is not a good fix.
good luck