One more idea.
Is it possible to update the XS8 firmware via PC with Windows 7 and firewire card?
Again, you don’t know if you need to update the IEEE1394 firmware. If you connect the XS8 to a Windows PC, Open the Control Panel and read what version it is. That would help. Then you can determine if it needs to updated.
You have stated that the Motif XS8 firmware is 1.60.x
The IEEE1394 firmware should be 1.07 but we have yet to determine that.
I have the same trouble connecting my XS8s to my MBPro. They connect to my XF8s just fine. The XS8s have lost all connectivity via mLAN. This is troubling as I had been touring with Neil Diamond and often, the rental companies did not have the Optional FW Card installed in their XFs so they could only offer XS machines that had the cards installed. I ended up having to ditch the FW and reprogram the entire show. However, I am still using the protocol in the studio for the XFs..
MLV