I've got a USB PS/2 keyboard/mouse adapter.  It worked fine for a very long
time, including earlier today.  Suddenly, it no longer works very reliably:

1. The mouse stops working entirely.  My built-in mouse (this is a laptop)
stays functional, but the USB-connected mouse dies off.  If I unplug the
adapter, and plug it back in, the mouse comes back for a little while - then
dies again.

2.  Sometimes, after a while of use, the modifiers on the keyboard stop
working reliably.  Once again, the built-in one stays fine, but the
USB-connected one is not reliable.

Anyone seen anything like this?  I'm inclined to blame hardware, but I figured
I'd ask before doing anything drastic.  :)

-s