NodeJS errno 37 on socket.connect

I'm trying to connect to multiple hosts in succession, this is the code to resolve the ip address and socket.connect() to each domain name (line[1]). This works on it's own but returns an errno 37 error when run in quick succession with different hosts. The best information I have on the error is:

" code: 'EPROTO', description: 'protocol error' "

Code:

$.connect(port, line[1], function() {
  this.write(request);   
});

Error:

{ [Error: connect Unknown system errno 37]
  code: 'Unknown system errno 37',
  errno: 'Unknown system errno 37',
  syscall: 'connect' }

How can I resolve this / why is this happening?

Thanks in advance.

EDIT: removed manual dns lookup code and added error report