utc.greekpool.eu probably would have the best ping for you.  idcray has poor ping.  See above for failovers;  maybe try;  greek, leet, minepools, idcray.

Also, in case you haven't make sure you add --expiry between 5-10 (default is 120) that could help if not set already.


Side note:  Leetpools back up. 

Idcray, greekpool, coinsnipers, and minepools were all stable through this