KVM Switches

Hi,
Im looking for a KVM switch that I can use on thin client devices, obviously I need a USB KVM but we have bought some belkin 2 port kvm’s with built in cables in the past and had nothing but problems. We’ve only used them on Compaq T20’s but we have a number of S30’s and imagine we will have similar problems.

Basically, the problem is that when you switch between devices the device that your no longer using thinks the usb device has been disconnected and the device you switch too thinks you’ve just plugged in a device. This is obviously down to the way that the KVM switch works but it causes a big delay between switching and being able to work while it detects the device(s) and also often causes display corruption on the T20’s as they dont like things being unplugged and plugged back in while working.
Additionally the KVM crashes quite often and wont work until you unplug it from the devices and then reconnect it, you need to do this as it doesnt have a PSU and instead draws its power from the USB ports on the computer.

So… Im basically wondering if anyones had any experience using KVM’s on any thin clients and if there are any particular devices you can recommend to avoid the problems listed above.
Thanks
Matt