i have a q-2221 american dj battle mixer (10"). My crossfader is not filtering the opposing channel as well as i want it to. how can i fix this problem or improve it without buying a new crossfader?

Does it help to move the fader closer to the sides? Or do you mean that it is already to the very side? And how old is it? And Have you replaced the fader before?

If the fader is worn, their is nothing else you can do, than get a new one. If you don't like replacing faders, try looking at the American DJ Q-D5. It features an optical fader, and is most likely not to let you down. It may be a bit pricey to you at first, but it may just save you a bundle in the long run.

I'm not sure I understand what you mean by not filtering, care to elaborate. . . you can always contact Tech Support at 1-800-333-0644 . . . you may just need a replacement crossfader.