Herman, nice system! Consider tweaking your battery with about 50,000uf of small electrolytic caps in parallel across the battery terminals, and a .1uf RELcap or V-Cap teflon bypass cap across power at the DAC PCB. This should significantly improve all aspects of the Altmann's performance.
http://cgim.audiogon.com/cgi-bin/vs.pl?vaslt&1140494870&viewitem&o12
Dave