I had this problem, what you need to do is simple. If you are on windows, click the start bar, click the search bar, and search up cmd. Once inside of CMD I want you to type, ping mc.piratemc.com.

It will have all of this mumbo jumbo about how many packets are sent and stuff, but what you need to look for is the line where it says, pinging (numbers)

Get the numbers and switch out the mc.piratemc.com on your minecraft server list, to those numbers.

That should work, if not then I cant help you.