Various problems with steam

Hello,
we got two problems with our game on steam.

  1. If we start the game over steam, the black engine console window shows up. It’s only happening when starting over steam, not if we start the exe itself.
  2. If the players want to use the steam voice thing, it claims the game is using the microphone and it fails. But we don’t have anything related in the game.

Any ideas?
Thank you!