My 07 avalanche has bose s s intermittent sound on left channel

You can replace one but I would go ahead and replace both. The wear is going to be on both sides and it will not be long till the other needs to be replaced.

There comes a small snake camera that you can adapt to your cell . Or loose your trany snd the converter an push it back a few inches

Hi:
I'd suggest you check the power steering for fluid level and leaks.

if its the doors then the seal on the speakers is letting water in and shorting out the speaker and causing the other speakers to do the same as the amp is being overloaded over time you will need a new radio as it will blow the amp in it. safety device will not keep saving the amp.

the handle sticks
or the brakes drag?'

Sounds like a fault with either the fuse board or a damaged wire somewhere along the loom i would go for the fuse board first and try taking a fuse out for the headlights and the side lights ect and chhecking with a meter to see if any current is present on the opposite side to the fuse

First Visually check all your fuses. Does rig have amp for stereo by any chance? It sounds like amp is bad and/or fuse is blown. Amp is wired between radio and speakers, and a shorted amp would make crackling in speakers when radio is OFF

I think you may have a problem with your electric assisted power steering motor. Is the loss in power only when your are making sharp turns to the right or left?
Do you hear any load noises or squeling sounds?
You should have it inspected, Don't want you to lose control while driving.

both rear door lock actuators need replaced I have done hundreds of them

You might want to suspect a stereo amplifier. Does your car have DSP? In any case, look in the trunk on the left hand side. You will find your radio amplifier back there. It will have about a 3in connector with a bunch of twisted pair wiring. Remove the connector and make sure there is no water contamination. All sound processing takes place in the amp.