I recently had a problem where my Arch Linux Fn sound volume keys quit working. I looked high and low and could not find a solution.

head space and timing

This is a military term related to ensuring the bolt and head space for the M2 .50 caliber machine gun are in alignment. This must be done correctly, or the weapon can explode during operation. It also means a person who’s screwed something up because they failed to check what they were doing before they did it.

~ head space and timing, Urban Dictionary

I noticed about three weeks ago that my soft volume keys no longer were working on my laptop. It was shortly after a substantial Arch Linux update, so I assumed it was due to an update of something. However, that turned out to not be the real reason my Fn sound volume keys quit working. I searched and searched all over Google, and I ran into some rather spurious advice (most, thankfully, I ignored), so here the reason my Fn sound volume keys quit working, and it may save someone out there some heartache.

However, here is the weird part: The toggle for the wifi still worked. If that were not the case, I would feel even dumber than I do right now. Since I rarely used the other keys, it was only during troubleshooting that I noticed that only the wifi toggle worked, and even in retrospect I think it should not have.

Anyhow, we have various colorful ways of expressing the type of error that led up to my Fn sound volume keys quit working. “That’s a user error.” “The problem is between the keyboard and the chair.” “It is an eye-dee-ten-tee (ID10T) error.”

After spending a few hours trying to figure out what was going on, it became obvious that pressing [Fn]+[F1] was bringing up the help screen. None of the other function keys were doing anything consistently meaningful, but that was pretty consistent. I then tried pressing [F1] by itself, and it muted the sound!

I never really paid much attention to the little lock symbol under the [Esc] key, and I always assumed that it locked the screen. Well, if you look closely at it, there is “Fn” in the lock. I guess having cataracts made this less than obvious. So, I pressed [Fn]+[Esc], and we are back to working normally.