I have this EXACT same issue. Have spoken to over 15 techs and had one come to my home to "diagnose". No progress has been made, and no follow-up from Xfinity. What are we paying for?
This sounds like something that will need to be investigated by the advanced techs and engineers. In order assist you, please send me a private message verifying your first and last name, street address including city state and zip code, and the full account number or phone number associated with your services.
To send a private message click on my name "ComcastChe", then click private message me.
Was a solution ever found for this? I'm having the same issue and have had 3 contacts with support so far to no resultion. Would greatly appreciate some assitance.