Looks like the tension of the belt is lose, the belt touching the plate on the bottom and causes the noise.
The belt can be adjusted, need to remove the cover on the right hand side of the printer (where the control panel is).
Is it just that one screw? On the other side of the metal plate? That screw is screwed in tightly
We had an issue where the spring/bracket that holds the pulley that the belt goes around on the right hand side was bent for some reason. Replaced and no issue.
Was is noticeably bent? Ours looks like its still in good shape.
yikes. did you have a terrible head strike leading up to it?
being a former programmer, error checking is everything. i have to think something led up to this.
im sorry for your problems. this is why we always run two printers. not so much for the throughput, but for the redundancy.
We have had everything you could think of happen. One point the SOL (Colour Sensor) had had its brackets broken off after a jam. Didn't notice for a bit so that was hitting too. Had to remove the cover and place it back in with velcro tape.
When was the last time you lubricated your carriage rails? Have you removed the little felt pads on either side of the carriage that ride on the lower rail and hold the oil? You might be surprised to see how filthy they are.
We lubricate often enough, it's only supposed to need twice a year but we do it far more often than that. We have taken the pads out before and soaked them to try and remove all the ink but can't seem to do it. I think we might have to order a completely fresh pair from somewhere.
Also, this happens less often during actual printing, were its severe enough to quit. Mostly during initializing, tests, and loading the paper does it crunch to the point of an error and we have to shut it down (sometimes right from the back).
Also #2, After long runs (20ft or more *ish) It asks me to reseat the M/LM printhead (spot #5 usually), which then leads to the alignment/test which then leads to the crunch.