No audio from door speakers only subs

Just yesterday I went to the store when I got back in the truck I had no audio. the head unit is on and works fine and the subs work as the bass of whatever is playing in the radio is hitting. But no audio from the door speakers. The truck came with an in dash milion brand and I think boss aftermarket door speakers and tweeters on the dash. when I came home with it I already knew it was a piece of crap. It's slow and bad graphics the cd/dvd doesn't work nor the iPod connection no gps only radio stations Bluetooth and sd card, even the rear camera has to be turned on manually through the head unit lol takes forever to read the sd card but it did its job so I was just going to wait till it crapped out which I think it did because of the problem I'm having. Took it to a stereo shop and they said it was the head unit because my subs are still playing, but My subs are hooked up to the head unit via rca's and remote wire so im not sure Im not big on radio electronics more mechanical stuff so not sure how to tackle this one. I've already taken the stereo out and checked for any ripped cut wires or loose connections and everything is good. And it isn't a hack job they used a harness from what I can see.