Controls crackle when turned
Your guitar’s control ‘pots’ (short for potentiometers) are mechanical, and have a limited lifespan. However, before you change them, it’s worth giving them a clean, as dust is often the crackly culprit. You’ll need to get into the control cavity and locate the dodgy control.
The metal casing for your control is exactly that – the hard work goes on inside, and that’s what we need to clean. Take a look at the back of the pot, and you’ll notice a small hole.
Get a can of contact cleaner, attach the straw to the nozzle of the spray can and squirt it into the guts of the pot. Give the pot some vigorous turns for 10 seconds or so, and you’ll hopefully find any dust has been dislodged. This can also work on crackly pickup switches.