Car Speakers

I recently bought a Chevy Tahoe and haven't had a chance to put a new stereo system in it yet. My other car I had a Kenwood system put in so that I could have Bluetooth access. With the truck in order for me to listen to the music on my phone through the radio I'm using an auxiliary cord. For some reason the sound is extremely low when I do this. Now when I'm playing the radio by itself the sound is loud. I'm not understanding what the problem is. Any advice?


Been there. I think, but never really tested the theory, that some devices initially lower the vol when the headphone jack is activated. I may be way out there.