My radio changes stations and volume as well as switches from CD fm am or off all on its own .
Sounds like you need a new radio (pun intended)
OR… does this car have steering wheel controls for volume and station change? Very possible those controls are worn out and randomly switching. Same solution, replace the radio, it is cheaper than replacing the steering wheel controls in a 10 year old car. The steering wheel radio buttons won’t work anymore but at least the radio won’t randomly change itself!