i have been having the same issue. I just upgraded my router to an ac1200 and I saw some increase since I live in a two story house and it is hard to get connection all the way across. The thing is it isn't consistent. I will peak at 68 mb/s but drop down to 500 kb/s. Most download and upload. Sometimes my upload will be faster than my download speed. I understand peak hours but this issue has been happening for a while even after we moved. Even when directly connected to the modem, i experience sudden drops making things like gaming online a nightmare.
Cox from Las Vegas, Nevada.