>Oddly changing from Umbrella to Google resolved the DNS issues, but the bad connection to Dashboard persists on and off
I have seen this before for customer using the free version of Umbrella (basically when you just use the OpenDNS servers). The more users and kit they have the more likely it is to happen.
My personal guess is Umbrella implements a rate limit for free users and when you exceed that they block you for 60s or so.