08 pacifica base stereo no sound
 

i have an 08 with a base radio, no factory amp, all radio functions display on the radio, all steering wheel controls change the radio display, the stereo icon lights on good stations but no sound. i bought a used ebay radio from a seller that matched the model number of my radio for compatibility and it is the same, everything seems to work but no sound. if you turn the unit off and back on you get an initial thump from the speakers. i turned off the park assist since it will mute the radio when the sensors are detecting. I am hoping someone knows what is muting the sound system and how to reset it. all i see in the posts are replacing radios and amp problems my situation is none of that.