Of course I did. They say they have problems but don't share enough information.
I will tell them to refresh their node list, as krnlx suggested.
The "bad" nodes are getting banned for misbehaving by good nodes and getting isolated from other net. So they can't sync and become "good" nodes. If You have nodelist with "bad" nodes and sync from them, you become a part of "bad" network, and gettin isolated. Like here : Sayman_nsk wallet bans "good" node(suprnova) for misbehaving :
2017-08-01 06:14:58 ERROR: AcceptBlockHeader() : extended invalid chain
2017-08-01 06:14:58 ERROR: ProcessBlockHeader() : AcceptBlockHeader FAILED
2017-08-01 06:14:58 Misbehaving: xcn.suprnova.cc (0 -> 100) BAN THRESHOLD EXCEEDED
He's probably on a fork, hence why he bans good nodes.
If this is the case, he needs to clean his peers AND blockchain.