I believe questions similar to this one have been asked in the past, but none of them seem to help me directly. So, I have a macbook pro and an RCA tv. The tv has an HDMI input so I purchased an HDMI cable and a Dynex Mini DisplayPort HDMI Adapter. When I hook everything up, the tv just shows the purple starry background that you see when at user selection when you start up your mac. How do I change the settings to get the display to show on my tv? It worked at one point, then it just stopped.