What was found
(CAN) AFTER DEPARTURE, THE FLIGHT CREW RECEIVED MULTIPLE FLIGHT CONTROL FAIL MESSAGES, WHICH SENT CASCADING FURTHER MESSAGES. THE FLIGHT CREW ELECTED TO RETURN AS A PRECAUTION. THERE WAS NO ADVERSE PASSENGER REACTION. ON CLB ABOVE FL340, AVNX MAU 3A EICAS AND ASSOCIATED OTHER SYS FAILURE. RETURNED DEPARTURE IAW MOC & FLEET REQUESTS, PROC 4, 5, 6, NIC 5 & 6 RESETS PERFORMED. IF NFF, REQUEST BY FLEET TO REPLACE NIC + PROC MODULE 5. REPLACED IAW AMM 31-41-04. CHECKS SERVICEABLE.