KVM Mouse prevents PC startup

Hello all.
I have a weird problem with a system.

I have a wired Aopen USB mouse, and a logitech PS2 mouse. I also use a self powered airlink 101 4 port KVM to connect to the computer. The mouse connector at the back of the computer is a ps2 connector. I put an adaptor on the usb mouse and connect this to the PS2.

The KVM works well with several other systems.

If I connect either mouse directly to the back of the computer the system starts.

If I connect either mouse through the KVM the system will not start. The PSU fan does not even turn. The only indication any power is getting to the system is the CD ROM light turns green on the front of the system and stays on.

Anyone have a similar experience?
Any suggestions?
tkman