The biggest issue Cox has with Contour 2 is that its not a Cox product, so their support for it is pretty poor. Its really Comcast Xfinity that is licenced and re-branded.
RDK-03033 is a network issue that is causing your primary box from talking to the Cox servers. Your internet is 99.9% the culprit, but most people think its from the CATV since that is where its manifesting and the internet seems to be working fine. Though on your end its not the best and your VoIP (cable phone) is also not working well.
Unplug all, and I do mean all, of your cable boxes, then reboot your modem. After your modem is back up reboot only the primary box and see if it works. If it does, the problem should be solved. It if doesn't you likely have an internet connection issue and you should focus on that. You'll be wasting your time trying to fix the TV service as that is not what that error code represents.