CM1000 Speeds Dropping to 1mbps w/ Xfinity

[JifferWap]

Hey There,

Moved about a week and a half ago. Got gigabit. Tech came to set it up, worked fine for roughly a night. Then it dropped to 1mbps or less speeds. I still had internet but called Xfinity and the guy had no idea how I had internet because my modem was not online on his end. He took it off, re-added it, and instantly it shot back up to full speed (about 350mbps on Wi-Fi, 980 on wired). All week it has been full speed. Today, since I'm working on my new house, I turned off the electric. When I turned it back on, the fastest I could get was a handful of mbps. Called Xfinity again and this time, pulling it off the account and back on did not fix it. I went to Best Buy and exchanged the modem for a new one thinking it might be faulty. Got home, swapped it out on the phone with Xfinity, and same speeds. I have an appointment for a tech to come Tuesday but what could be causing this issue? 

Here are some pulls from the modem:

[vkdelta]

is it at 1Mbps right now? If yes, what are the counters showing? 

Are you testing it directly hardwired to Laptop or via Router?