How do you fix your inspiron 531 speakers when you put your headphones in the jack they work but when you just use the speakers they wont on the sound levels they say that the speaker is working?

The problem is in the headphone jack. It has a switch that shuts off the speakers when you plug in headphones, but that switch is stuck on. You will have to have the jack replaced if it is built in to the motherboard or on a connector on the front of the tower, or you can replace the sound card.