you could push them to re activate the SH2 if you still have it - depends on what package you are one but some have got them to allow then to go back to SH2 even on speeds that are said not to be supported
I've run some diagnostics from here to see if I can spot any reason for that speed but I'm not currently able to retrieve the Hub power level data. Would you mind browsing to your Super Hub's Interface pages and posting the data for me?
Navigate to 192.168.0.1 in your browser
Don't login, click on Router Status, top left
On Upstream select the Power Level (dBmV) data
On Downstream select the Power Level (dBmV)
Paste the data on here please.
I'd also like to know if your speeds are from devices connected via wireless or Ethernet.
Heather, you keep giving people this advice the problem is Hub 3.0 does not work with VPN's its a software issue i don't know why your recommending all this stuff the 2.0ac works fine i know because i spent weeks with the 3.0 doing all this stuff pulling my hair out till i discovered change to old router bingo works no messing about with DMZ or anything else until you fix the software on Hub 3.0 PLEASE advice correctly on it being firmware issue.