New-SCVirtualDiskDrive causes the NIC's to disconnect

Hi,

I've got a PowerShell script which adds some additional VHD's to a database server using the following PowerShell command -

'New-SCVirtualDiskDrive -VM $GuestServer -Path $VHD2CreatePath -FileName $VHD2CreateFileName -Size $VolSizeMB -Fixed -SCSI -Bus $BUS_ID -LUN $Next_Lun_ID -RunAsynchronously'
                               

Whilst this command is running the VM loses connectivity and all NIC's switch to being disconnected.

Is there a parameter that I need to add to my command to stop this happening or is it a bug within VMM?

Any help would be greatly appreciated :)