We experience freeze ups, buffering, skips, &etc. This issue has been occurring since 2013 using numerous versions of browsers, xfinity apps, even OS versions. I have the luxury to even use current computing platforms with ample-to extensive memory and resources. From tablets, to laptops, to desktop form factors. Win7, Win8x, and Win10x. Our 200MB pipe to the internet has never "cap'ed" and usually hovers at 5% utilization up/down, and never more than burst 30%. ( Not Comcast... I should mention). Xbox, Roku (etc) performs almost flawlessly. In comparison they ARE flawless, with an alert or undesired event occurring only once every few days, not every 5 minutes ( or even less) on Comcast/xfinity in comparison.
Frankly, I have not executed these same stream requests on our Comcast backup circuit which is only a 50MB pipe. However...due to the regularity of simple internet / dns / bandwidth interruptions, we are certain any results will be similar, due to these simple known outages. Thus why we have a 200MB external service provide for stability and reliability. We no longer monitor our Comcast circuit for the simple fact we are dispatched numerous alert messages that cannot be resolved. No amount of new routers or docsis modems on our side by Comcast tech level-0 supports recommendations ever correct issue. No cable issues are ever found on the 40 foot drop from the pedestal or the single 30 foot run from the customer service side of the connection, on the facility block. We don't even leverage the CATV portion. Hmmmm let's look into dropping that service now that I think about it! Our Juniper & Cisco enterprise class routers switches logs fill with Comcast errors. Our low end consumer class ASUS, Cisco, Netgear exhibit the same but with much less capacity, configurable options, or error conditional handling.
Now that I've taken ample time, passive aggressively praising other providers and services over Comcast/xfinity, we can't conclude any thing different than Comcast/xfinity is garbage and the support is nil; AND no amount of exhausted energy and good air wasted attempting to resolve something that Comcast prefers not to correct. *Now sit back, and is there anything else that can be helped with, like selling you some channels you don't really need and will frustrate you even more when they too go offline, or help programming your remote controller????