Realtek device keeps appearing in notifications, but can't identify.

I've recently been getting notifications of a "Realtek Semiconductor Corps" device joining the network. This can happen up to 3 times a day, and I cannot identify the actual device (I've given all my others friendly names). 

The really odd thing is that the mac address changes every time the device connects, so I can't block it. Also worth noting that it doesn't use much bandwidth at all, so I can only think that it must be a smart home device. 

Has anyone else experienced this issue?

6 replies

    • cMoo92
    • 2 yrs ago
    • Reported - view

    My guess, based on it being a Realtek network card, is that it’s a Windows 10 computer with MAC randomization enabled, which will make eero think it’s a new device each time. Check out this link for more info: https://www.mathyvanhoef.com/2016/03/how-mac-address-randomization-works-on.html?m=1

    • gazzza182
    • 2 yrs ago
    • Reported - view

    Thanks for replying. I do have 2 win10 pcs in the house but they’re both off. If I block the device, it pops back up again within seconds. Really weird. 
    also it’s transferring minute amounts of data (220kb). 

      • eero_support
      • 2 yrs ago
      • Reported - view

      gazzza182 Hello and welcome to the community!

      If you are willing you can do some testing by changing your wifi password and connecting one device at a time back to the network to see if you can identify which device is allowing this Realtek device to connect. 

      It is a long process but you'll eventually fine the device with this method.

      James Wilcox

      eero Support

    • Scott_Chapman
    • 2 yrs ago
    • Reported - view

    I've found Fing to be really useful for this sort of thing. It seems to do the best job I've seen at identifying devices. I believe they combine MAC address lookup along with their own crowd-sources database of refinements.

    • gazzza182
    • 2 yrs ago
    • Reported - view

    Many thanks for the replies! 
    I did manage to narrow it down in the end as I have 3 eero’s and I knew which one it was connected to. I’d also named the majority of the devices attached (quite scary to see exactly how many devices there are!). 

    As it turns out, it was a set of WiFi LED lights that were causing the issue. For some reason the unit kept power cycling, and every time it rebooted, the MAC address changed (never, ever seen this before). I replaced the module and the problem has now been resolved. 

    just to say, the eero units are brilliant! My internet connection has never been so fast and stable, and I love the ability to name the devices and organise them.

    Thanks again!


      • osvaldas
      • 1 yr ago
      • Reported - view

      gazzza182 Hello, maybe you can share WiFi LED lights model? I work with networks and I often see that new devices appear with "Realtek Semiconductor Corps" on routers. So we just want to buy those WiFi LED lights and validate if they caused that issue.

Content aside

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  • 1 yr agoLast active
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