Stock Audio System Going Crazy

[Hickory]

So my audio system has been acting a little screwy recently. For the past few months it has stayed on after shutting off the car and opening the door. I thought that was a little weird, but nothing that I can't live with. Then two days ago all my bass went out. There is a slight tone change when I go from the highest bass setting to the lowest, but it is minimal. I have a subwoofer, and my amp is getting power, but there is no output from the sub. I don't have a voltage meter on hand, but I am going to test the RCA tomorrow when I can get my hands on one to see if it is receiving any signal from the head unit.

When I turned on my tahoe today, I had no audio from any speakers even though the headunit was powered on. I turned the tahoe off and back on and it went back to the no bass audio.

Any ideas what my be causing this? I have a 2005 tahoe with the Bose system and stock touchscreen head unit.

 

[Hickory]

Update; I pulled the head unit out and checked my connections. Everything seems to be fine back there. I can hear my sub power on and off when I turn the truck on, but still no signal from the head unit. This is leading me to believe it is a head unit problem and not a bose amp problem.