So we upgraded to Gigabit about 3 months ago and everything has been great with pretty much full speed all the time with the SB8200. A few weeks ago(I understand the timing is probably correlated with COVID), we started experiencing severe ping/latency issues that could only be resolved by a hard reset and then there would be a few hours of decent connectivity. This did get better but now I notice that I have not gotten faster than 300Mbps in the past two or three weeks. I've made a few calls and online chats about this issue and so far have not gotten far. Online chat did say they would send a "truck roll" around but that was a week ago and I've yet to see any difference. When I check the modem status page I see a large number of uncorrectable code words and considering nothing about my topology has changed this leads me to believe it's either a Comcast signal issue or perhaps an overcapacity issue. Is there any hope of being credited on my bill for this? Seems a bit ridiculous to pay for GIgabit speed and only get 1/3 to 1/10 of that in practice.
I felt the same way after moving to a new house. I was getting 850-950 down with my SB8200/RT-AC88U combo (running Merlin) at an apartment in Oakland for almost two years before I initiated the transfer to my new home in Petaluma. On the transfer day I plugged in my rig and hardlined to the modem and I immediately saw 950+ so I was feeling positive. I then activated the service at the new location and suddenly I was seeing 95 Mbps! I let it sit for a while in case the activation was still doing its thing but after a couple days despite all my efforts, and regardless of how I was connecting (ethernet or wi-fi), I was strangely getting 94-95 Mbps, as if there was a brick wall. This made me very suspicious so I called in.
The technician I eventually spoke with wasn't sure why I would be seeing 1/10 of my service speed, offered no diagnostics of their own, and immediately escalated the call to...Arris! That person had me do a full reset of the modem and router but I was still no better off. I was still seeing exactly 94 Mbps regardless of device or connection method. I called yet again and that person recommended the new XB7 gateway as my solution. Again, they didn't offer much in the way of help or diagnostics with my existing equipment which was disappinting. I'll admit I don't knew the network particulars of my new area yet so yes, perhaps my existing setup wasn't ideal so I accepted the offer to try the XB7 free of charge.
I received it yesterday and now I'm seeing nearly the same speeds I saw at my previous location. I still find it awfully suspicious that my speeds were so severely and consistently capped, with the only solution being to replace my perfectly good equipment with Xfinity's. They offered it to me free of charge though so if this continues to be stable I suppose I will be needing to find buyers for my previous setup.
That would make some sense but this equipment worked just fine for a couple months before everybody started working from home. I specifically purchased equipment from the recommended devices page and I highly doubt it's an issue on my side given the timing of things and the numerous other users complaining about the same thing.