P1S Belt Abnormality?

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I just finished printing a 3 day TPU print, and I reconnected my AMS and tried to print a simple picture frame for my wife. When it got about half way through the print, the printer started making weird grinding noises moving along the X axis. I thought this was particularly strange because I just (less than a month ago) did a full maintenance routine on the printer following Bambu labs guidelines. I then recleaned the graphite rails and relubed the Y rails, and ran a calibration cycle and I didn’t hear anything, but on further inspection of the belts they look a little different, and I’m not sure if it is normal or not, so I thought I would ask.

There is a little brownish orange section on the top of the belt, and I am just curious if that is something I should be concerned about?
Would that cause a grinding noise?
Another possibility for the grinding noise could be when it was doing infill. I was using Sunlu PLA+, which this printer seems to have a few issues on its basic settings. Could a poor infill pattern and a poor filament make a grinding noise?

Any help would be appreciated!
RP