Good stuff that Counterpoint gear. The 5.1 has a cult following and for good reason. Other products such as the SA2 had similar issues with the PS. I got my SA2 PS rebuilt with updated parts and the wimpy external transformer replaced with the Plitron. The Plitron update especially made an improvement that could never have been expected. I suggest that you contact Mike Elliot about some updates for the 5.1......starting with the Plitron. If you're good with a soldering iron, you could update many of the PS parts yourself.
John
John