HDMI on MacBook Pro stopped working The HDMI port on my MacBook Pro doesn't seem to be functioning normally.

When I plug it into the TV, the screen temporarily turns black as if it is connecting to the TV, the mirror connection even comes up and I can see the other display (My Tv) and change the settings.

However, on my TV it shows a No Signal message. What is the reason for this? When I hook my Xbox 360 up via the same port, it works flawlessly on the TV. This leads me to believe the is a problem with my laptop. It was just working a couple of days ago, and detects the external device just fine. What is the reason for the No Signal/black screen issue?
could be a hdmi cable issue
maybe restart your computer. in OSX 10.9 Mavericks has some issue with dual monitoring, restart without the video cable plugged in . once its fully started, try plugging in the video cable again.