Speakers disabled

Question

i have an acer extensa 5220 orignaly with vista basic but it was heavy (vista)and slowing the use of the laptop so i opted for windowsXP pro it is very good but i have problem to get sound since i have to use an usb headset to hear music or what ever and i wish you help me get back the use of the speakers wish are disabled with the vista (vista is just disabled not erased)
thanx in advance