connecting to localhost is slow when any network adapter is connected

Question

I'm talking to mapproxy web server through localhost on windows 7. The talker is my own WPF program. The target ip is 127.0.0.1 and the server listens at 0.0.0.0:8080. When ANY adapter connects to anything the communications are super slow.

I have read through this and this where the answers point to editing hosts file which I tried but to no avail.

I tried installing a loopback adapter as instructed here which only made things worse as then an adapter was seen as connected and connection was super slow. I was thinking of defining a loopback adapter with a different loopback ip but the adapter dissapeared. Maybe I'll revisit this train of thought.

I have tried with both localhost and 127.0.0.1 as the target IP and localhost, 127.0.0.1 and 0.0.0.0 on the receiver. They all work but end up slow when any adapter is connected.

I tried with hosts file to point both IPv4 and IPv6 localhost to the IPs (removed the comments) and tried IPv4 alone with IPv6 commented out. I tried everything again with restarts between each change.

I looked at the communications with wireshark and I see alot of NBNS queries. So the IP isn't found properly and Net Bios requests are sent out instead? Might be something with one of the libraries I use...

I'm abit stumped as to how solve this problem. Any ideas?