ukbd: short freeze when activating LEDs

I recently switched from a PS/2 keyboard to USB.

Whenever I press capslock/numlock, the system shortly (< 0.5 ms) freezes. The 
LEDs are switched on/off after that short delay. This also happens when I 
switch between virtual consoles using ALT+F[0-9].

Using a USB->PS/2 adapter, the keyboard doesn't show that behavior.

Otherwise it is working fine.

ukbd0: <vendor 0x046a product 0x0001, class 0/0, rev 2.00/0.26, addr 3> on 
usbus0
kbd2 at ukbd0

This is on 8.0-BETA4/i386.