Connection unpredictably swaps between InternalDNSName/Proxy/PortForward

[CornBread81032133]

I've been using this for a few weeks now and I'm really pleased that someone has taken the time to show some love for linux users. One issue I'm noticing is that it appears to unpredictably swap between connection types on file read which leads to varied performance. For example, when copying a 10ish GB file it will begin at true LAN speed, then adjust to a far slower speed as low as 700-800 KPPS (greatest sustained speed of my connection with upload/download in use), later on it will then adjust back to LAN and increase up to full transfer rate. This can also vary with sometime being full and others being slow.
What conditions need to be met for it to swap connections? Also is there the possibility of adjusting the code to have an Internal only/LAN version as I'll only use it on LAN.
I've attempted to refactor the code however I've got little experience with Golang and can't get the correct syntax to work.