I agree with Lynn (GTPDad). Also, you might considering checking the voltage reading on the battery statically and dynamically with a multimeter including charging system with engine running. Since the radio seems to be affected the 12v in IGN MAIN 1 could be low or loaded down. It feeds just about everything including radio power, engine electrical controls/PCM and the fuel pump. Troubleshooting the problem may require some patience and further testing to further isolate. In a worse case scenario you could have a defective ignition switch assembly. Good luck!