I just received my Line 6 DL-4 back from Robert Keeley's shop. He offers a service where he essentially removes much of the backround noise and annoying little quirks of the pedal such as clicks when engaging it, volume changes when it's on vs. when it's off etc. Upon first plugging it in I have to say I was hard pressed to hear the difference...until I compared it to a stock unit (I work at a music store). It was still a subtle difference but noticably quieter and cleaner. While the quality improvement of the signal path would easily be enough for me to pay for the mod it gets better. When I got my unit back and plugged it in it had.....BLUE LEDs!!! So in addition to removing annoying RF noise and bug fixes, my tone no longer suffers from the effects of red LEDs. I'm a very happy customer.