I have a question about a Universal I hand press. The problem first became noticeable after setting the rollers to the correct height and printing for a while. The back inking roller gear will sometimes jump off the track when in print mode and make a terrible sound. We were able to replicate the problem by raising the roller by the gear and ‘printing’ with no ink on the press. There seems to be some wear on the track by the gear because of this problem. How do you think this could be fixed? Maybe the rollers, because of vibration, change height? Or can the rollers swell and cause this problem? The serial number on the press is 25748.