2004 Kia Sadona - radio or fuse/electrical problem?

I have a 2004 Kia Sedona with 61,000 miles on it. Over the weekend my radio/cd player stopped working. I checked the fuses by taking each one out and replacing them. None were blown and the radio once again had power.

Today, I drove a short distance with my car and stopped and shut the car off. When I got back in my car, the power to the radio was off again.

I went back to the fuses and check them. I pulled out the audio fuse, it was fine and replaced it. There were two fuses that I had to press down because they were not in securely. I feel there is another issue here, please advise me on what the problem could be.

The dealer thinks it is a radio issue that is not under warranty, of course.

Thank you