Looks like Wolfram's neighbor found out it was leeching wireless and put a WPA key on it.

It could be that new hire in cubicle #2 downloading Hello Kitty Tea Party. Wait, I bet it's that guy who still doesn't get The Sixth Sense so he's downloading it again. I got my fingers crossed for him. You did not elaborate into how efficient your network is but rather just ask for a new company by insisting that the shared plan is to blame. I'd stick my head into the network and figure out why delay is increasing. If all else fails, I find that a reliable jitter is the best and letting the network traffic produce the jitter is not the best idea. Let me know if you want more information on this. Sorry, I can't answer your question because it is a satellite connection. I feel everyone's pain.