Miscellaneous C554E showing Off Hook

I have a C554e that randomly shows its off hook. Updated firmware, re-seated connections, reinitialized fax boards and did clear all data. I also turned off the option board on both fax lines because customer isn't using them yet and it still happens. IT shows up about once a week and locks up the copier cant get it out of fax/scan mode must reboot copier. Tried hotline they said they had 1 other instance of this happening but ticket is still open. Any suggestions would help.

Thanks