The HDMI port on my Satellite L500 laptop is not sending information to my sony bravia tv. All was working fine up until a couple of days ago. When i plug the hdmi lead into the port, it seems as if the laptop is aware it's plugged in as the screen flickers. The fn +F5 keys do as they should, but no picture appears on the tv. The tv shows a lead is plugged in also and again the screen flicks to say a source is there but then remains black. I can't see an issue in device manager and all drivers are saying they're up to date. I have also tried a new hdmi lead but nothing. Can anyone help with this?