@Naoecla
I've just answered your report about the round ending prematurely, but by checking this report here now I'm sure you're referring to Hero Showdown in both reports. Hero Showdown is the 2v2 mode you're referring to. Heroes Vs. Villains is a 4v4 mode with no rounds whatsoever, whichever team has 35 deaths first loses.
Now, addressing the issue you're reporting here, this can happen in 1 of 2 ways:
1st - Both teams have 1 player each, which will make the countdown run, and if a player joins the game as soon as the countdown is over, the match will start as 2v1;
2nd - Both teams are full, however one player is still in the loading screen, even though he already appears in the lobby for the other players. The game thinks the player has already fully loaded, but that isn't the case. Due to that, that player can't spawn, so the game just doesn't give any character to him, and the match starts 2v1.
I'm very familiar with the second case because my PC is a potato and my loading time is too long. More often then not the first round of Hero Showdown starts with me as an spectator and my teammate having to face 2 enemies alone. There's nothing one can do about this except getting a better loading time for the one who struggles to load this game.
