Last month our group lost the first three rounds of a Counter-Strike 2 match because one player's microphone had quietly switched to a laptop webcam after a system update. Nobody noticed until round four, when somebody asked, "Wait, can anyone hear him?" By then the economy was gone and everyone was irritated. Since that evening we run a very small voice test before anything else happens.
What the test is
Each person says one sentence at a normal speaking volume, and the others answer with a single word in chat. The sentence does not matter; I usually read the first line of whatever is lying on my desk. What matters is that all of us hear all of us, on the devices we will really use during the match.
The three weak points
The first is the wrong device. Operating systems like to change the default input after an update or when a headset is unplugged and plugged back in. The second is the level: a quiet microphone makes the speaker repeat everything, and a loud one makes the whole call turn its volume down. The third is the push-to-talk key, which now and then resets after a game update. Sixty seconds of testing covers all three.
Order and manners
We test sound before anything else, because a team that cannot talk cannot solve any other problem. If somebody has to fix a device, the rest of us wait and do not start the queue. We use the time to fetch water. Nobody is blamed for a broken microphone; it is a cable, a setting or an update, never a character flaw.
Keeping it short
I once turned the voice test into a small ceremony with a countdown, and it grew into five minutes all by itself. The rule now is one sentence each and no commentary. If a device needs more than a minute of repair, that player joins late and the others warm up on their own.
Where it belongs
Sound is only the first line of our routine. The remaining steps, covering the game client, the crosshair, the map pool and a quick stretch, are written down in this five-minute check before our CS2 group presses queue, and the sound step is the one that has saved us most often.