FYI - Comcast sometoimes does their equipment maintainability and servicebility between 1:00 AM to 6:00 AM and this might be what you are being impacted by. If you could obtain upstream and downstream, SNR power levels during this timeframe it would be helpful to post those here.
Heh. So the customer gets to do comcast's monitoring for them? I guess the last time I had business internet service, the NOC would let me know that there had been an outage... I never had to tell them. Why do they call this "business" class service? There isn't even a way to call the NOC?