radio volume issue (2012 base model)

I've noticed that when I try to turn my volume up, it doesn't always work. I turn it to the right and the indicator will go from 17 to 6 and then I have to keep playing with it until I get the level I want. Sometimes it will work if I turn it slowly but then I'll get to a certain point and the volume will drop again.

(truck doesn't have steering wheel controls, stock single CD radio)

Is there a fix for this or is the fix to buy another radio?

(do not want an aftermarket radio)