I recently bought a mini displayport to hdmi adapter with audio support. I connected this and a hdmi cable between my macbook pro(purchased feb 2010) and tv. The video worked fine but the audio was still playing through my macbook. I went into system pref>sound>output and the only option available was the internal speakers. The tv speakers had not been detected. I tried reconnecting, rebooting, and other tvs. Any advice as to why the audio won't play and why the laptop won't recognize that other speaker options are available? All reviews on this adapter said that as long as the macbook was purchased in 2010 then the audio would work.