Acer H213H No sound

Question

Hi, I have recently purchased this monitor with built in speakers but cannot get them to work. I am using the HDMI cable with an adaptor to connect the monitor, as I've read so far this could be an issue as the HDMI cable can also carry sound. Though in this case the sound would not be coming from the video card port (this is the case with people trying to hook up to PS3/Xbox). If anyone can help I would be very appreciative.