If you play say Kelvin in the lobby and you que and join a game as Kelvin. Then your build does not automatically que at the start of the match (even if the option is enabled).
If you play a different hero in the lobby than in the game you join it does work.
Valve please fix
So when the character Billy starts "sprinting" you don't hear footsteps, you can only hear his footsteps briefly afer shooting or jumping but once you start walking a bit faster and he puts his gun up on his shoulder he becomes quiet.