The H8000FW has 4 AES outputs on the back, but the manual talks about 8. How can I get access the other AES outputs?
The other 8 AES outputs are on a DB25 connector on the back panel. This is a TASCAM format, and suitable snakes to connect to it are available from various sources (e.g. Digidesign). See the User Manual for more info.
You could also use the analog output or S/PDIF.
The Speaker Settings for the Dice driver will probably not be helpful.