Please look into this; last week service was very slow and later went out, and Comcast did repairs, but service is extremely slow again. See attached for a comcast speed test. I'm getting between 2 and 5 Mbps download, 11.5 upload. I'm on a 50Mbps download, 15 upload business plan. I've had very slow speeds for weeks though.
P.S. I saw a similar posting on this forum from another San Francisco customer from last month. An admin replied to ask for the modem's signal levels. I will preemptively add here that my modem doesn't seem to show signal levels in any of the pages in the config screens.
So I will say that that particular modem has a known packet loss issue that COULD be tjhe root of your issue. Many people report that having Comcast swap out the modem for an SMCD3G or a Cisco DPC3939B clears the issue up immediately.
In any case, signal levels should be viewable by browsing to http://10.1.10.1 and logging into the Netgear with username=cusadmin password=highspeed , and then clicking the links on the left-hand-side of the page.