Same exact issue here I even upgraded my modem and router and was told the same exact thing even with 7 or so techs coming out to "help" me. Looks like cox is giving customers the run around instead of making any serious improvements or changes to the network. The COVID Congestion issue is most likely a factor but considering the pandemic has been going on for a year now and the amount of people actually staying at home is far less now I feel this is a go to excuse instead of them actually taking a deeper look and finding a solution since its easy to just blame a pandemic they cant control. Regardless of if it helps I would strongly suggest making an FCC report about this since its the only thing that can be done to hold cox accountable.