My volume only works when I either am using iTunes or a bluetooth speaker. How can I fix this?

The title is fairly self explanitory, I cannot hear anything from my computer speakers, it wont even have sound when I plug in headphones, but oddly enough, it works with bluetooth speakers.. To make things stranger, It also works with iTunes, but iTunes only.. I cannot even hear the little noises that happen when you lower and raise the volume via the buttons on the keyboard... Someone please help with this. Thank you.