Comcast said the first time our netgear modem may be too old, even though it was a docsis 3.1.  We got a motorola a few days later and had the same issues.

They came back a few weeks later and replaced the old rg58 drop (they should have done that a long time ago)  and ran a new cable from the pole all the way to the modem outlet. Signal improved, dropouts slightly improved but still goes out for minutes to an hour. 

A week later they came back again, replaced a port on the pole and adjusted the DB down a little. But didn’t make any difference. On the comcast board someone said that motorola may have a firmware issue causing all the errors on the OFDM channel.

 So we got the SB8200 and this one too is having dropouts and the log is full of errors. Comcast says everything looks fine on their end.  It’s doubtful we had 3 bad modems in a row. 

All these errors are just from just 2 hours of uptime and we are loosing connection every 5 minutes now.