Good morning all this is a very unusual issue on a Mx-7580 and recently lost our support from sharp but my job is still to fix the machine

- I am getting the Black registration pattern on back of single sided prints - followed on next page by the CMY registration patterns

all drums are relatively new and clean - both belts are new - registration / calibrate sensors under belt were just cleaned and drum grounds all have fresh dielectric grease

did 44-2, 50-22, 44-27, 44-6, 44-26, 46-74 all with no issues after cleaning

Has anyone seen a similar issue or know which board would be generating this pattern?

Thank You all in advance for your assistance!!