Cant mount when USB debugger is on

[droidkevlar]

So I thought this issue might have been ROM related but seems it is not. So far on a clean install of Cm RC3 or SS 4.7, for some reason when I plug my phone into 1 machine, only way to mount is by turning USB debugger off. The machine is Win 7 Pro x64. I didnt have any issues last night when working on my Win 7 Pro 32bit machine.

Anyone have any insight of why this is happening?

I had a NAND of a fresh install with my settings, so I will flash back to that and see if I can still mount at my home computer. But last time, this carried over the NAND restore.