Lost MDD Timeout

For the past three weeks, my household has been experiencing intermittent internet drops. At first I thought it was due to the maintenance Comcast said they were doing around 12/29 in my area, but the drops persisted after the maintenance was complete.

I called Comcast and set up an appointment for a tech to come out, and he stated that the signal was strong enough and encouraged me to replace my 5 year old cable modem.

I replaced my modem, and the internet drops continued intermittently. Throughout these drops, both modems continued to report "Lost MDD Timeout" events. My family and I are frustrated by the random internet drops.

Comcast, can you please assist with some more in-depth troubleshooting?