My bad, previously I linked the firmware for the 7830, 7835. The correct link is here for the 7845-7855.
I will edit my previous post as well so it doesn't make for an issue down the line for someone else due to my incompetence. Sorry, hope you don't have a download limit.
Call Xerox, get to 2nd level, try convincing them not to ALTBoot the device and see if they can help resolve it.
The Altboot would fix it assuming the device is the problem and not the client submission method, but the reason it happens on yours and nobody elses if all settings are normal would never be known.
You don't want to jump on the Altboot though because it wipes the device.