Ive got me the Digital Nasties

In my experience, the AC cord is the first tactical move against digital nasties then come AC filtering.

Trying to manage your audio cables so it doesn't cross with one another especially with powercords is a freebie tweak that works too.

Other than cables, this recent thread is helpful:

http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1051384332