Clixx13

Hi, I have a Klipsch Promedia 2.1 speaker set for my computer (and it's fantastic!) that I've been using for well over a year. I got it second hand from a friend of mine, and it performs extremely well, but we've both experienced the following problem: When adjusting volume with the volume control knob, there are what I guess I can describe as bands of static, much like tuning an analog radio. I have to adjust the knob just right to get a desired sound level and quality. I was wondering if anyone else has ever had this problem and if there's anything I can do to fix it.The speakers have not been modified, damaged or mistreated in any manner. Thanks!