Restart the software. Can you try directly connecting one of the publicly available nodes using the 'addnode' command? Node list:
https://bitnodes.earn.com/.
Yep! Already try, with about 30 of them, but no better luck. Sometimes got 2 or 3 peers, but they gone in a while. And the "socket recv error" remains a lot.
You sure that the port isn't blocked in a way, say by your ISP?
No, the port is ok. I've tested it from other networks, and my ISP ensures network neutrality
BTW, I can run other coins (eg monero) and the btc testnet works fine for me.