I have had a bit of an intermittent issue with my Bronica SQAi where I have been getting some lines on my negatives.

Initially, I thought it was scratches, but I am not sure. The lines are dark on the negative, where's if they were scratches, they would be clear. (obviously, they print as white on paper). The other thing is they tend to not be in the same place, but appear to be similar shape.

Below is one specific example, scanned in as negatives, accompanied with a zoom into the spot.

Anyone got any clues?