Hi, I had this same problem with 3 controllers and the below is quoted from RDC. He gave me this advice and I just replaced all of them and I had sucess. It synced. So, I am not really which was the culprit. This is a good start and it work. THe 80 pin was really hard to put back on after I got the old one off.
Good luck
I messed with one of those and ended up having to replace the MCU (the 80 pin QFP) to get it to sync up to a console. It could be the SIC chip or the EEPROM too though, the SOIC8 chips on the board, but the one I messed with those did nothing and the MCU had to be swapped to get it working, I even swapped the RF module but nope, it was the stinkin MCU. (This is quoted by RDC.)