Injustice 2 - Internet connection causes performance issues

[caped.mario]

I got Injustice 2 on Steam a short while ago, and I've been having performance issues with it right from the off, which puzzled me because of my specs -

GTX 1070
i7-4790k @ 4.00 GHZ
16 GB RAM

However, after trying out all sorts of solutions, I think I've found the problem.

I disconnected my PC from the internet and started again in offline mode - lo and behold, the game is running properly. However, once I connect my PC online again, even with Steam running in offline mode, the performance problems are back.

So it seems connection to the internet is causing these problems. Tried connecting to a different hub, using a wired connection, etc. - no matter the connection, the game lags like a mother-fifer.

So I figured out the problem, now I just need a solution. Does anyone have any suggestions? Outside of playing the game while disconnected from the internet (which isn't really ideal), I'm kind of at a loss.

 

[natx808]

try and run the game windowed connected to the internet and take a look at task manager -performance monitor
while you are playing, look at processes that might be eating up your CPU, or processes that are consuming excessive network bandwidth