Dh13

Hey guys, I've been working on a 2004 Mazda 3, the 6 disc cd changer will no longer eject or play cds and some were stuck but everything else worked and you could hear the cd player trying to eject. I was working on getting the cds out for someone and once I put the radio back into the car and cut it on the radio and the display no longer work and nothing plays no radio or cd. I can still hear the cd player trying to eject the discs. Any ideas on what might have happened to the radio or what I should look for? Thanks