External Monitor Flickering (monitor is fine)

Hi.

I've got a Samsung monitor connected to my MacBook Pro. It's been fine since I first connected it 6 months ago.

Recently however....

- when I start up my computer in the morning, it flickers after a few moments and then the screen goes black.

- if I disconnect it and reconnect, the same thing happens.

- i repeat this process for about 2 minutes and finally it "sticks" and I can use it.

Troubleshooting:

- I've ruled out the adapters and cords.

- I tried both ports.

- I even ruled out the monitor. I connected another monitor to my MacBook and have the same problem. Both monitors work fine on my other mac.

- I ran the latest OS update.

Any takers? 🙂