I have exactly the same issue. I lose Internet and TV every night between 8:30 to 10:30 PM.
TV image starts freezing
Internet starts becoming very slow.
Motorola cable modem downstream signal levels start going outside allowed range > 15 DBmv
SNR(Signal to noise ratio) normally at 39 DB plus goes down to lower 30
No change to Upstream levels
Then I lose TV and internet. Outage duration varies from a few minutes to over an hour. Then it woek fine for the next 20 hours. I get dowload speeds of 180 Mbs download and 12 upload.
Xfinity sent technicians 4 times to my house and can't find anything. I have been telling them they should look in the equipment in the street. I guess they just like to come to my house. Another visit (4th) scheduled for tomorrow.
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