Black screen connecting via HDMI to Plasma

You may have to reset the resolution settings. To do that you need to do the following:

• First, totally power down your Xbox One by holding the power button on the console for 5-10 seconds. Don’t just tap it; hold the button down.
• Next, turn it back on by holding both the disc eject and power buttons for a good 10-20 seconds. This bit is key: don’t release the buttons when you see the Xbox One light come on; instead, continue holding the buttons until you hear
  a second chime. Also, just keep an eye on your TV screen/monitor — hold those buttons down until you see the green Xbox One start screen.

After you did these steps, go to settings and choose the correct resolution for your TV or monitor.

Hey Buddy..

My family has the same type of TV..

My family has the XBox One S on it everyday..

My father plays game on the same TV for over 8hrs.

Yep, the port black out sometimes too

I have a old cam on the port.

It goes black on the ports

when connecting a HDMI cord with laptop.

After that the port do not act rights.

We fixed by turn off the TV.

Every time you connect any HDMI Cable you have to have to turn TV off.

Once you added the HDMI then turn the TV back on.

If you plug in or take out any HDMI Cable off the TV the ports will go out.

Make sure you have a ethernet cable connected to the internet the TV may need a firmware update. Its an old TV but still may need a update. try a factory reset on the TV ONLY. Make sure its connected to internet to firmware updates.

Sorry to say your port are getting badly weak just like my family tv. One day my ports may not work.. I have to remind family turn off the TV to add any cable connections.

I highly recommend taking it up with the official, friendly support xbox support staff. Do know however, that they've been swarmed with questions the past few months, so it may take a while before your question gets answered by them.

I suggest you use the green "contact us" button on the right side of this page.

Hi SailormoonGirl6, thank you for your suggestions and taking the time to prepare a detailed response for me. Sadly I have tried all of these recommendations but I still don't have a display from my Xbox, only my laptop.

Thank you for the suggestion Jeroen, the green 'contact us' button was my first port of call but they will not take telephone calls or emails on this subject and recommended I posted in the forums.