Crackling faders and pan pots are a common problem on mixers of all types, and they are often the result of excess dust or age. While you may want to replace crackling faders and pan pots in the future, it can be a costly repair. However, there are some stopgap measures that will fix the problem temporarily if your problem is severe, or permanently in mild cases. Though this is a fairly simple task, you should never attempt any repairs on your mixer if you are unsure how to perform them.
Turn your Mackie mixer on and note any faders and pan pots making a crackling noise. Note them on a piece of paper by channel.
Spray compressed air into any faders making a scratching noise to remove dirt and debris. This may not solve the problem, but in mild cases, it can often get rid of crackling noise. If not, proceed to the next step.
Start with the lowest channel numbers making a crackling noise. Move the fader or pan pot from the lowest volume point to the highest volume point or from left to right for two to three minutes. Use about the same speed you would when regularly moving the fader up and down to avoid damaging the fader. Repeat this step on all offending faders and pan pots.
Turn the mixer off and open the first channel strip with a Phillips-head screwdriver and locate the fader inside.
Spray a small amount of special fader lubricant into the channel strip. Allow the fader section to dry for 20 to 30 minutes before reinserting the channel strip into the console. Repeat this step for all offending faders, allowing each to dry before reseating them in the console.
Open the first channel strip with a Phillips-head screwdriver and locate the underside of the pan pot where it connects to the fader.
Spray a small amount of switch and contact cleaner onto the pan pot. Turn the pan pot from left to right for two to three minutes. Allow the pan pots to dry for 30 minutes before reseating the channel strips in the console.
Special fader lubricant and switch and contact are available at many electronic supply shops, professional audio supply stores and through numerous online retailers.
Never work on your mixer when it is turned on. You could damage internal components and there is a risk of electrical shock.