Inconsistent/high loaded latency issues since speed upgrade.

I've been directed to post in this forum, so here is a copy and paste of what was written.

"i have posted before about the ongoing issues being experienced since we have upgraded service, issues that I have now detected to be caused by an extremely unstable/high loaded lantency problem that appeared alongside the upgrade to our services. 
on the low side we get around 90ms on the high side it will shoot up to 900ms. It's never consistent, tests done seconds from one another to the same locations (no matter what distance) will jump from double to triple digits.  
this is affecting every device as it's just the "new normal" for our connection.  Calls lag, games lag...everything lags. 
this was never an issue before the speed upgrade and move to the new gateway, this house was also completely new wire job last year" 

please do not post another link to an xfinity help artlce...they are basic trouble  shooting that we have already been through a million times.  I'm looking for help, not to waste my time wasting yours.