Time Warner Cable is Not Neutral Toward CDN Traffic

I’m a Time Warner Cable (TWC) cable internet subscriber. I pay ~$100 a month for whatever their fastest internet speed option is in my area. My Eero wifi router will regularly report speeds as high as 130 Mbps down and 30 Mbps up, which would be great.

However, I have had constant buffering issues with any video streamed over my home network. Netflix shows, movies streamed from iTunes, and the most frustrating of all, videos on Instagram all experience terrible load times, buffering, dropped connections, etc.

I’ve noticed that essentially any data obtained from a content distribution network (CDN) will experience these issues, while traffic from other sources has no problems. As evidence of this, I can show ~30Mbps down from Speakeasy’s Speedtest:

…while 10 seconds later, Netflix’s Fast.com shows 7.8 kbps:

Tier 3 TWC tech support insists the problem is my local network. I’ve gone through three modems, and 3 high end routers (currently on an Eero), and all setups show the exact same issue. Can anyone propose why my local network would treat CDN traffic differently than other internet traffic? Is this even possible?

If I’m correct in saying this problem is on TWC’s network, this is essentially a violation of Net Neutrality, even if it’s inadvertent. I don’t think it’s fair to advertise 80 Mbps down if the most common source of internet traffic (Netflix) is experiencing 7.8 kbps down.