Not working

So I got a polksb5000. Problem is I only got the bar. I found a power cord that turned it on, connected it to my phone and the lights are blinking on the bar, saying it was connected and then green for everything is working correctly, but there is no sound coming out of the bar. Do I need to order new parts for it or is it broken probably??? I don't want to order new parts for it if it doesn't even work... Please let me know if I am doing something wrong. Thanks