You can purchase the channel faders directly from Mackie Service Dept., you can replace them yourself if you're good at soldering - HOWEVER, be advised that disassembling the unit to get at the faders to replace them will require a lot of time and patience if you've never done it before. If the faders are not moving smoothly, it's possible that the wrong type of cleaning spray was used on them and there's a possibility that they could stop moving and controlling sound.