I'm using a Xante Ilumina DPP 502 with a DEP fuser installed so we can run envelopes a little easier. We bought the machine from another printshop that was closing down and we don't have a service contract. My issue is that we have only recently developed a problem with the machine. Up until a month ago we had no problems with it outside of the usual color matching that comes with any laser printer. But now, if we run a standard #10 through it, we get lines not included in the graphic. First it was just a vertical line (parallel to the short end of the envelope) but now it's a horizontal line as well. The vertical line is a small faint double line (side by side) that fades in and out as the run proceeds. The horizontal line is a mix of all the colors and comes in always 3 quarters of an inch from the lead edge. I've managed to prevent it by switch from medium weight on the machine to ultra heavy 4, which runs slower than a snail and really flattens that envelope. Is this an issue with the imaging drums or the transfer belt. Our drums and toners are all fairly new, we bought them from valley litho. Any help would be appreciated.