AI 2015 very slow on VPN and connected to server

hi all, i've had the following problem, wonder if you know what's happening? (i notice this on large AI files, it may happen on smaller ones and i don't notice)

i have a 31 MB AI file, it has a large raster image linked, not embedded, in the background, then vectors on top of that, then a bunch of small raster logos on top of that. the logos are all embedded. if i am at work, i can open and manipulate the file fine while it's on the server.

when i connect from outside of the office, i'll usually have the above files (the AI and the large base image) copied to my drive. i can open the file and it's nearly instant when moving logos/ doing vector work.

IF i get on the VPN and connect to the server (say to grab another file or a new logo), the performance in AI becomes insanely slow. moving vectors or logos takes many seconds. if i open the above AI file while connected to the VPN & server, AI will be slow to open the file. if i use the mac force quit action (cmd-opt-escape), the window will show AI is not responding and is crashed.

everything is fine until i connect to the server. i can be on the VPN and it's fine. keeping in mind all the files are local or embedded in the AI.

my solution is to NOT be connected while working, but why is this happening?

thanks for any input.