E120 / AIS Problem

Hi All

We recently purchased a new to us Trawler. It has Raymarine E120 & E80 MFD's, radar and auto pilot.

I noticed that the software on the MFD's was about 4 Revs levels out of date. So after much effort I was able to get both MFD's to the latest/last revision.

The new problem now is the AIS is not showing any target data. A RED X on the AIS icon on the display. Prior to the upgrade the AIS worked fine. No re-connections or wiring changes were made. The AIS is a SR 161 receiver connected via a Brookhouse MUX.

I have verified that the MFD is set for AIS 38400. I can find no other setting within the various menu pages???

I have also verified that the AIS is streaming data via computer and Open CPN.

Any suggestions?

Thanks