A few things overnight...
I see no changes when wired to the router, with a device IP in the DMZ or via an incognito tab in Chrome browser. I'm not running any widespread security suite, though I do not recall if I restarted the router after disabling AiProtection - something to try during the next period of downtime. I'm not running ad-blocker, VPN or QOS and various fresh browser installs reproduce the same behavior. All three router bands are merged together into one SSID via "Smart Connect" if it matters.
The various page source links above complete tracerts but I do see a line of "* * * Request timed out." with tinygs.com, fonts.googleapis.com & static.cloudflareinsights.com. cdn.jsdelivr.net shows no issue.
The ISP device is a plain modem wired directly into the Asus RT-AC5300. I see the "MAC Clone" button in WAN settings under the Internet Connection tab - I can fiddle with that next.
The router lists firmware 386.11 with signature 2.362. Maybe the signature auto-updated this week and isn't playing well with this router? Wondering if a hard reset via WPS button, fresh flash while wired & another hard reset would brute force a setting back to the stone age. A number of the USB Applications used to be enabled by default but have not been in recent factory resets via the GUI so maybe its holding settings somewhere. I don't mind wiping it out and rebuilding if beneficial, though it often results in evil looks from the wife & kids...
Again, greatly appreciate everyone's help!
So not sure if you tried this but bypassing the router completely and plugging into the cable modem into your computer directly via Ethernet can tell you if the issue is related to your isp or router. [
Edit: you did] If you’ve done that and it loads fine directly connected to the modem then it’s the router if not then it’s an issue with your isp or it’s modem.
If it’s the router, setting the router to factory default or using the asus router web ui or recovery tool to reflash the firmware and make sure its clean couldn’t hurt if nothing else fixes the issue.
I’d also maybe try some different Ethernet cables to your isp modem and or computer in case a bad cable is causing network related packet loss. Although it’s unclear to me how many sites this is an issue for you with.
If you’ve reinstalled your browsers and cleared browser cache it doesn’t seem to me like it’s a browser issue.
Things to try speedtest.net check your isp speeds to make sure that they are around your rated isp plan in terms of speed. Check if there is high latency or packet loss on the speed test.
Not sure what the tracetrs time-out error is about maybe post a screenshot of it so we get a full picture. (Remove your ip if it shows) And do a ping test to the specific site like tinygs.com (not sure if that’s what you meant showed no issues).
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Edit: You could try to disable smart connect and have your wifi radios have different ssid’s although I’m not really sure if smart connect would cause this usually it causes issues with connecting in general to your wifi when their is a problem.
Mac clone is sometimes used with cable modems and isp that require “authorized” devices only be used in other words your isp keeps a list and any device not on the list is denied; Mac cloning impersonates the authorized devices MAC address to bypass this. So Mac cloning is unlikely an issue if your devices reach the internet.
I would set DNS Director’s global redirection to Router also to force all devices to use the routers dns as shown above.
I would also verify DNS is actually being sent to only the dns addresses you set and not defaulting to isp dns servers. Check
https://www.dnsleaktest.com/
Lastly only other thing maybe coming to mind is maybe by some off chance TTL is timing out too soon. But I’m not really sure. ]
Others might have more suggestions.
