Asset Import and Data Collection not detecting Machine is Domain Controller = True

Greetings All,

I have a net new CCS 11 implementation.  I have noticed that the asset property of "Machine is Domain Controller" is not getting update on 5 of the six domain controllers.  In other words, of 6 domain controllers, CCS is only detecting one of them as Machine is Domain Controller = True.   

Has any body else experienced something like this?  What attribute/characteristic is CCS looking at for that field? 

SCU = 2013-1

PU=2013-2

When I Query the value Is PDC (Browser) that value is returned 'True'.  When are Query Machine is Domain Controller it began to return True, after I added the Is PDC ... field to the query.  However, doing another Asset Import or Data Collection after that querty had no effect. 

Any thoughts?

Thanks in advance for any help.