The power to the radio among other things cuts out for second then comes right back? Sometimes it does it out of the blue other times exactly when you dim the headlights. Also noticed the gauges bounced at the same time once. My son drives it so he sees the problem more than I have. I changed the cigarette lighter relay (which the radio power goes through) also changed the headlight relay & the dimmer relay. Any help would be appreciated.

 

Shake the key while the engine is running. If that causes the electronics to act up, then you may need a new electrical portion of the ignition switch.