or better yet, stop using IP Addresses that keep changing and use hostnames that will always be correct?
cache?.winmxgroup.com (? is 1-9)
cache?.winmxgroup.net (? is 1-19)
put a few random ones in, currently every hostname points to every cache, but that can change so multiple hostnames is a good idea (plus i believe robox will only try the first if you only put 1 hostname in, multiple hostnames will make it try multiple times)