Psychonauts fails to start on Ubuntu 12.04 x64 with the error
SDL_OpenAudio failed: No available audio device
What do I need to do to start the game?
The Psychonauts port to Linux is only released in 32bit and requires that some sound libraries are installed.
Open a terminal, or if you wish look for the package in the Ubuntu Software Center, and install
sudo apt-get install libpulse0:i386
After you have done so the game will start normally and the sound will be working.