Our 5-year-old house came prewired with Cat 5 to a panel in the basement. Our CenturyLink ISP connects to their router there. Service is 40 mbps down, 20 up, and Speedof.me tests show we routinely get around 45 mbps.
Every few days, my wife’s 2018 iMac gets “not connected to the Internet” messages and delays when using Safari to read her Yahoo mail or play Facebook games. After a few minutes, the message goes away and data flows normally.
My Mac’s in the basement, connected via a Netgear Powerline that runs data through the electrical wiring, getting 46 mbps, and I never get these messages.
She’s connected directly to the Cat 5 system on the ground floor, via a flat Ethernet cable, about 20 ft. long, running under the baseboard because her desk is on the opposite wall from the wall socket.
Last night, after all Internet use was done, I did speed tests using both speedof.me and CenturyLink’s speed testing website, and all looked pretty good.
Because I suspected the flat cable, I ran tests with a MacBook Pro using that cable, and also going directly to the socket with a normal 6-ft. cable. Both tests, on both websites, got around 45 mbps. CenturyLink’s test showed”ping” of 4, while Speedof.me showed “latency” of 33 with the flat cable and 14 with the normal cable. (Are ping and latency synonyms?)
(The Powerline only got 15-18 mbps from her work area, but she’s farther from the router than I am in the basement, so that makes sense.)
Could something be wrong with her iMac that would cause it to lose connection (or think it’s lost connection) intermittently? I ran the Hardware Test and it found no issues.
Of course, good data speed doesn’t mean some connection’s going bad, then fixing itself after a few minutes. But wouldn’t that be a wire that’s barely making contact somewhere, and wouldn’t that affect speed all the time?
Could the CenturyLink router be malfunctioning? We’ve also had recent buffering issues with our Roku stick. Two nights ago, I restarted the router, and immediately all was fine. Unfortunately, my wife also turned the Roku off and on, so I don’t know which rebooting fixed the problem. The Roku’s in a spot that tested 44.5 mbps last night. (This wireless Roku may be a separate issue, since my wife’s wired iMac trouble has been going on for many months.)
Mac? Wiring? Router? What (and how) should I be checking?