how to ignore <XF86Launch1>s?

[jidanni@jidanni.org]

Every day before my computer is completely warmed up / dried out,
it sends phantom <XF86Launch1> key presses to emacs, causing
<XF86Launch1> is undefined
<C-XF86Launch1> is undefined
etc. (The latter was when I was holding down CTRL planning to press
another key.)

In emacs how can I ignore these, via keyboard-translate-table?
I don't want to bind them to a function as they could occur at any point
e.g., C-x <C-XF86Launch1> etc.

I already use an additional USB keyboard, and in
/usr/share/X11/xorg.conf.d/66-jidanni.conf I already do

Section "InputClass"
        Identifier "Bypassed Busted Keyboard"
	MatchIsKeyboard "on"
# IBM Example, but can't use symlinks
#	MatchDevicePath "/dev/input/by-path/platform-i8042-serio-0-event-kbd"
	MatchDevicePath "/dev/input/event0"
	Option "Ignore" "on"
EndSection

to stop other phantom characters, but that doesn't stop the phantom <XF86Launch1>s.
No I don't want to buy a new computer or replace the keyboard.