These KVM are hardware related only and can not be firmware updated, neither using specific driver (Tiger or XP pro). Tried also the IOGEAR GCS632U USB KVM switch but I got the same issue. Complete PC Restore tool, 617 component/RGB video analog ports, 395 Component Services snap-in, 606 components (PCs) input devices, 6 KVM switches.
The STARTECH SV231USB 2port STARVIEW USB KVM SWITCH. The freezing problem is always when I'm switching back from the PC/XP to the Mini, never form the Mini to the PC/XP. This will cause unpair the device and switch the Pi-KVM to public mode before the first client is connected. If something went wrong, use the web menu System -> Reset keyboard & mouse. I HAVE TO (& DO) activate the KVM's Mac Mini USB port before booting Tiger to avoid the message window seeking for bluetooth devices (no keyboard/mouse detected). Once the server is connected, Pi-KVM will no longer be discoverable and pairable to other clients until you unpair the server. The keyboard & mouse are plugged in their KVM's USB specific ports. I disabled energy management features as well the screen saver. It freezes at least once a day or so (maybe (?) too early to say, less often under 10.4.2 ) but it still happen as it did under 10.4.0 & 10.4.1 The only way to escape from this Mini "frozen" status" is the hard reset & reboot (holding power-up button few seconds). Before Tiger (10.4.x), aka using Panther, my USB KVM let me switch back and forth between my Mini & the office's PC/XP.