MS510TXM LAN port randomly turning off

Hi- I've had the #MS510TXM for two years. This problem has existed from the beginning, but it would happen once/twice a year, gradually since then it's happening every day or two. It's always the port from the router. What's interesting is switching it an open port would resolve the problem (not exactly ideal) but now it kills every port I move the cable too. I was going to RMA the device but wanted to be sure there wasn't something that could be causing it.

-The issue was there from the beginning, however recently it occurs regularly 

-It's occurred with three different ISP's in two different states

-Occurred with 3 different routers

- I've replaced the cable multiple times, (both for troubleshooting and because of moving)

- I've done a hard reset of the switch and configured from scratch

- The other ports have never had an issue and it doesn't matter which port I use on the switch for the LAN, it's the  one that random turns off. That's what makes me wonder if there's something I have configured thats causing it.

Any guidance would be greatly appreciated,

Thanks