Are you having a specific problem or is there a type of improvement you are looking for?

Otherwise, my expectation is that the 990 should be able to support all of the technology claimed in the manual, but not beyond that. So for example, if the DD 5.1 audio specifications prior to the last date of new sales included a specific flag that had not been used until now and was unsupported, then I would expect a firmware upgrade. On the other hand, I don't think its reasonable to expect Outlaw to support HDMI on the 990 or provide video processing that was never part of the original product.