YouTube Buffering Issues with Cox TG1682G Panoramic Wifi Modem/Router

There is an issue with the Cox Panoramic Router/Modem and YouTube. I can't tell if there's a firewall setting or something I'm missing. YouTube videos buffer while using the Cox Arris TG1682G Panoramic Gateway.

I thought at first that Cox may be throttling YouTube so I got the FCC involved. I still suspect it, but haven't been able to prove it. However, when I put the Panoramic Modem/Router in Bridged Mode, and connect my own router to it, YouTube doesn't buffer and videos load instantly. Keep in mind that while using the Modem/Router combo in it's normal Routed/w NAT mode; that speeds were great overall. So it isn't a speed issue. It's YouTube in particular and videos taking 5-10 seconds to buffer before playing, only on Cox's network. This was tested on several different computers, and mobile phones with the same results.

I've changed DNS servers to use non Cox DNS, played in the router settings, turned off TG1682G firewall, etc. I can't think of anything else that could be causing this except Cox doing some sort of traffic shaping/prioritization, or throttling with YouTube coming from their device, or a TG1682G device setting.

Results were intermittent at times, meaning a few times videos would load instantly. That lead me to believe that it wasn't necessarily throttling, but traffic shaping/prioritization instead. Cox has denied those claims as well.

The only constant in all of this is the Cox Arris Panoramic Gateway.