flirc-se recycling boot and other strange behavior

I have a flirc-se to use with my htpc (ubuntu+kodi).  Everything worked
fine until I tried to program the remote control (harmony 650) to use
some hot keys (F8 to F12) I had added to the keyboard to switch between
kodi and various configurations of google-chrome (for different streaming
services).  After adding the hot keys to the flirc-se configuration and
rebooting the boot stopped after a few second (I could hear the fans
stop) and started again.  This sequence just kept repeating until I turned
off the power supply.  I then removed the flirc-se power switch cable
from the motherboard and reattached the power switch cable from the front
panel but kept the usb cable from the flirc-se connected.  The pc then
booted normally but the cursor behaved strangely.  When I opened a
selection window the cursor sequentially lite up the selections and I
could not select any.  Also when I opened a terminal window the terminal
kept cycling through the terminal history.  I could not log out of ubuntu
but had to turn off the power supply.  After disconnecting the usb cable
from the flirc-se the pc behaved normally.  Any suggestions, please.