macbook speakers

okay so i have this issue where they wont seem to work, i try to change the volume but i get like a circle with a line through it, it works fine with speakers and headphones but not when i unplug it

a few weeks ago it started working again... now its stopped, i can still here the start up noise of the mac btw

what could the issue be =[

Ring the store you purchased your computer from they will sort this out for you, its obv a hardware problem not something that you could fix.