[GAMEPLAY] Some settings are not taking effect at the start of a game.
The only one I know of (because it's noticeable) is mirrored scoreboard.
How to reproduce:
Step 1) Set your scoreboard to mirrored.
Step 2) Start a new game, press tab. Your scoreboard is not mirrored.
It is probably affecting things such as sound volume and etc as well (possibly even mouse sensitivity, since I saw a thread about that).
QUICK FIX: When the game starts, press escape to open the settings menu and press it again to close it. Your settings will now take effect.
EDIT: it might only be happening when I duo with voice.