Weapon icons not showing.

Just a little problem which is getting more annoying over time.
Whenever I press 1,2,3,4,5,6 in singleplayer and multiplayer, I have no yellow icons showing me what gun is which and there is no sound being emitted when I press them.

Anyone know a fix?

The most clearest solution is as follows.

** Go into garrysmod/ Go into “options”/remain in the “keyboard” tab/ click on “advanced”/ then make sure that the “fast weapon switch” is NOT ticked. **

Tell me if that works.