Okay, after hours and hours, I finally found a fix for this.
1. Disable UPnP on your router.
2. Go to origin
3. Right click on Battlefield 4 and select "game details".
4. Next to Launch options click "edit".
5. Under command line arguments, add " +clientport 2xxxx". Where "2xxxx" is a number between 20000-29999
6. Click "apply"
6. Do the same for all of the other computers on your network, just make sure the port you enter is a different number than the other ones.
7. Foward all of the computers ports you entered in origin on your router, and you're done!
