Headphone Jack Not Working!!!?

I have an hp pavillion laptop and my headphone jack wont work. whenever i plug my headphones in, the sound doesnt work even though the headphones work and the sound works on the laptop speakers when the headphones arent plugged in. whenever i plug my headphones half into the laptop, the sound comes through the headphones and laptop speaker. my driver is IDT high def audio. how do i fix my headphone problem? i even have the latest driver update