Volume problems volume auto adjust up wide open by its self loudness turns on and off by its self

When mine did this I opened the face up and figured out that the volume down button switch had a broken contact which made the volume and the first 3 station presets freak out. It took me about a half hour - 45 min. to fix it (since I had to diagnose it first) Won't cost a dime if you fix it this way...

First figure out if one of your volume buttons doesn't feel right when you press it (it doesn't 'click' or act like the rest of the buttons do)

When you open the face you 'll see all of the white switches (small boxes with silver surrounding the button on the top) take a tiny flathead electronics or eyeglass screwdriver (or something like that) use it to "pry" up the silver piece that surrounds the button (The edges on each end have a 'lip' that holds this metal piece down & you might need a magnifying glass depending on your eyesight.)
It will bend but you can flatten it back out.
Once it's off - the button will come out and if you look down into the 'box' of the switch you'll see a small piece of metal (the contact)
Use your small flathead screwdriver to lift it out. (or turn the circuit board over and tap it out)
it is a small rectangle piece of metal that has a 'bump' in the middle.
Check to see if the "bump" is split/broken in the middle. (mine was)

I then did this same process to the switch for the AM radio button (since I don't use it) then I took that 'contact' out since the 'bump' wasn't split and put it in the volume down switch, then I put it back together (using) the tip of the screwdriver to press the metal that was a little bent back down under the 'lips' on the edge and over the button.

Now you can put the 'face' back together and "viola"!!
It works properly, the volume doesn't freak out anymore, and you can enjoy a properly working car stereo again!