Thanks for your help. As it turns out my power is supplied by a PS600. It "grunts" under the load when the 750 is powered up. It either generates some noise or has a drop in voltage output. Either way, the B&K Ref 30 doesn't like it and the software seizes up. Changed the power source for the 750 and all is well.

Found a power strip made by Bits Ltd. It looks like a good product and can be found at www.bitsltd.net .