I know that my new 27" late 2015 iMac has a Thunderbolt 2 connector on the back and my TV has HDMI ports on it. Do I need to look specifically for a Thunderbolt 2 to HDMI adaptor or can I just look for a Thunderbolt to HDMI adaptor? Is there a difference? Also, will this connection transmit video AND audio? I am trying to watch a movie and display it on my TV. Thanks!