Hi kaveman,
Check out these knowledgebase articles about that issue and take a look at the related links for more information. Also, if you go to ni.com and search for "scxi auto detect" or some variation of that phrase you'll get a lot of hits with good information about that issue.
http://digital.ni.com/public.nsf/allkb/3CF19284F684224886256CB400682AB3?OpenDocument
http://digital.ni.com/public.nsf/allkb/FA32B0EAEEA81D2586256D5200693BD2?OpenDocument
Chris W