Hi,
I have a similar problem. I disconnected the battery and now every now and then when I try to turn the radio on I only get the "chrysler" display without any sound and none of the buttons are functional. It happened again today and I checked the fuses (5 & 8) and they look ok. Then I tried the radio again and it worked. We'll see what happens in the next few days.
Let me know if you resolve your problem.