as WhiteRav3n said, spirits are everywhere. you might want to work on balancing your chakra's, meditation, perhaps even cleansing your home there could be a build up of energy preventing you from sensing them.
regarding the board, while they are not evil, be careful. you might want to make/buy a new board out of wood or something other than cardboard. damaging a Ouija Board causes very negative effects which is why it's not wise to make one out of a flimsy material. [though you can] cleanse, charge, and store the board in a safe place. when you use it, cast a circle, and cleanse the area when finished. [a cleansing bath is a good idea as well]