Well - in the past (been a comcast internet customer for 11+ yrs at same location), I have seen DNS issues... whenever I would see 'looking up host' in my browser, I would change my DNS setting from DHCP to 'Use specific...' and use 184.108.40.206, since I know this is a publicly available DNS that was VERY reliable (plus its easy to remember).
I usually use that to ping and/or tracert whenever my service seems laggy or non-existent.
I'll admit that using this DNS was first tried a LONG time ago... perhaps I use try a different one (maybe 220.127.116.11)? Or is the 18.104.22.168 reliable enuff to use?
Sorry for the questions... Im not home right now, so its hard to test... Kiddies just informed me that the 'internet is SLOW'... I'll do more debugging when I get home.
I have both windows and linux machine at home... hopefully, I can resolve the slowness.
I'd at least call it in to Comcast to let them know you're having problems. We're mostly customers here. With all this rain, maybe something got wet. Or some critter nibbled it.
Other people here are better at interpreting the numbers, so I'll leave that to them. They might like to know about any splitters you have. Are you seeing similar numbers whether or not you have your router connected?