Stock Radio Not Working

I have a 2008 Aveo LS Sedan and I have no power to my radio. I checked all the fuses and they are fine. I pulled the radio out and checked the connections and they are connected correctly. The only thing I have done is take battery out to charge because the battery was completely dead. I received the car from my brother before he passed away. And was told that the radio has only worked once. Anybody have any ideas as what I can do?

If you have power to the radio and assuming it is the stock radio, we were able to get one working intermittently just by smacking the front face of it. Somehow this one lost connection to the front panel, and by smacking it would make contact for a while, at least until the next big jolt. May just be the radio going out. FYI