Hey all, just wanted to let you all what I've found. I've had a customer call twice about loud noises when running envelopes and cover stock through the bypass. What I found is the customer failed to change bypass settings to the proper settings. Causing excessive buildup of toner on the web at the web pressure roller. This excessive buildup was causing the web pressure roller to vibrate and bounce rapidly creating the loud vibrating noise. I simply advanced the web until it was clean where the pressure roller made contact and the noise was gone. I defaulted the bypass to heavy one to alleviate the issues and asked the customer to rn it that way to see if the noise returns. Of coarse I know it won't.