Do you have any USB2 plugs on your laptop? I vaguely remember people having issues with USB3 (the blue ones). Do you have the latest drivers installed for your Keyspan? I did have the same problem as you for a while, but I did get it to work eventually. I can't remember what I did. Also make sure the FW update is the only thing running on your laptop. It is very temperamental. I may able to find a copy of the beta firmwares for 3.09 ("j" I think) if you want to give that a shot.
Yes, I recall people having trouble with USB3 but that might have been with the ARC mic. Still worth trying a USB2 port, or real RS-232 serial port if you (sjcruiser ) can borrow an old PC.
Note: I can’t find any documentation about the port settings in the manual or firmware readme file, so I checked my old PC and I have Com1 set to: 9600 baud, 8N1.
I agree that firmware 3.09j is a good idea. It has some very important audio fixes for the 50v (and some more minor fixes for the D2v) so why Anthem never made an official update for the non-3D hardware is beyond me!