[Gameplay] Issue with camera and clicking

Mac [OS X El Capitan]

Upon entering a game, the camera becomes disabled and the only way i can use it is if i press and hold space, it then locks to me. Right click does not work and I also have to double click to do anything. I have tried every thing suggested on the internet to fix this without uninstalling and reinstalling, even then, after 2 games it occurs again and effects every subsequent game.