Dell XPS Laptop sound

I left my laptop running for about 15 minutes. When I came back and tried to play a music file, or any file that contained audio, the speakers don’t work. Not even headphones work.

I’ve noticed that only one of the lights in the speaker grill is on. I’m not sure if this is causing the problem though.

Please help if you can.

P.S. I don’t know any technical information about the laptop.