Assuming the switch isn't worn out, use a contact cleaner first. Deoxit is expensive for a small can. I just got an amp for cheap cuz all the pots had noise and were cutting out. I got WD40 Specialist Contact Cleaner, not the regular WD40. It's half the price and twice the size of Deoxit, and it cleaned up the pots just fine. Also, your local hardware will probably have it.