I run "xev" and left alt reads "Alt_L" while right alt reads "ISO_Level3_Shift".
I tried googling it and found this:
The culprit is as VF said: in /etc/X11/xorg.conf the option ' Option"XkbOptions" "lv3:ralt_switch" ' is written, and it should not be.
Edit that file with sudo privileges and put a '#' in front of the line ' Option
"XkbOptions" "lv3:ralt_switch" '
Save open documents and restart X (Ctrl+Alt+Backspace)
That didn't fix it.
I have a fresh install of Ubuntu Studio 9.10.
I also tried setting Keyboard Preferences, "Keyboard Layout Options", "Alt/Win key behavior", to "Alt and Meta are on Alt keys"... but that didn't work. So I put it back how it was.
There is, however, this interesting thing in the keyboard layout options window:
"Key to choose 3rd level" > "Right Alt" (is check-marked/enabled)
What the hell is "3rd level"? lol Anyway, I tried disabling it and it automatically re-enabled! (When I re-opened that window it was checked again).
So how do I get right-alt key to work?
And what the heck is the reason for it not working anyway? :-p
I want my "Alt_R" back!
Okay I set keyboard layout options to "right alt never uses 3rd level". My right-alt works now.
But what the heck is "3rd level"? At the moment it's not enabled. What purpose would anybody have for some "3rd level" function (whatever it is)?