Is there a way to reconfigure function keys on Ubuntu 19.04?

Question

I installed Ubuntu 19.04 on HP ProBook 450 G6 and noticed my function keys for increasing/decreasing brightness both act as toggling microphone, the rest works fine (and everything works fine on Win 10). I have two questions:

• Is there a way to reconfigure actions for those two keys?
• Is this a bug that I should report to Canonical?

Answer 1

1. open terminal and run xmodmap -pke | grep MonBrightness

example:

pratap@i7:~$ xmodmap -pke | grep MonBrightness
keycode 232 = XF86MonBrightnessDown NoSymbol XF86MonBrightnessDown NoSymbol XF86MonBrightnessDown
keycode 233 = XF86MonBrightnessUp NoSymbol XF86MonBrightnessUp NoSymbol XF86MonBrightnessUp
pratap@i7:~$ 

2. Copy the lines after = for both BrighnessDown and up

3. Once the keycodes for fn+f3 and fn+f4 are known

4. xmodmap -e "keycode xxx = XF86MonBrightnessDown NoSymbol XF86MonBrightnessDown NoSymbol XF86MonBrightnessDown"

5. xmodmap -e "keycode yyy = XF86MonBrightnessUp NoSymbol XF86MonBrightnessUp NoSymbol XF86MonBrightnessUp"

once you logout above commands 4 and 5 will not persist..

to make them persist follow this thread https://askubuntu.com/a/1131511/739431