Just to cover all the bases, the first step would be to go to the 990 and set the 7.1 Direct input to use the XA2's video connection (assuming you are using the 990's video switching for the XA2) and to then select the 7.1 Direct input ("7.1 D") button on the 990's remote. Check those out and let us know if there's still a problem - there may be something funny in the XA2.