Kiers

I hope someone can help! When accessing an application through the citrix gateway, if I disonnect the usb keyboard it displays the message: "The network connection to your application was interrupted. Try to access your application later, or contact technical support." And then logs me out. I have recently bought USB KVM switches and use one PC to access applications on the citrix metaframe and the other to access another application that doesn't use citrix. When I was switching between PCs, when I went back onto the PC using citrix it would display the message above. First thought it was the KVMs but later tried removing the USB keyboard from the machine itself and that's what the problem is! It does the same on both Windows 2000 or XP. I have tried playing with all the keyboard settings on both the ICA settings and on Windows and it doesn't resolve the problem. The bizarre thing is the PC doesn't lose network connection when citrix session disconnects. Has anybody had this problem before or able to help? Thanks