Mine is doing the same thing. For some reason the laptop is connecting to the weaker network and not the one that is stronger. See attached.  I have to disconnect and reconnect to the network every 5 minutes or so. Very annoying. I even put the Eero in the window of the bedroom that is literally within view of where I am sitting right now and it's still having issues.  I contacted support and it went nowhere.  I have a printer in a back bedroom pretty much right above the Eero unit in the basement and it refuses to connect to the one in the basement instead its connecting to the unit in the upstairs bedroom through a cinderblock wall; as you can imagine the printer is offline quite a bit.   None of my devices are roaming properly. I have an Eero I the garage and when I'm outside I have almost no signal despite standing on the other side of the wall where the Eero device is.  I tested the beta firmware and it did not help. 

Came home tonight my Eero was telling me there was no internet connection. Strange because my desktop which is connected through Ethernet was working and could browse the internet just fine. None of my devices would connect to the wireless network at all. It would just fail to connect. When it did finally connect it was very, very slow. Speedtest.net loaded slowly and the connection was so poor the actual speed test would not run and my ping was 45ms which is not good considering I'm in the bedroom 10 feet from the Eero. I discovered that my MacBook connected to the garage Eero across the yard despite me being in the same room as the Eero I should be connected to. Also, the MacBook doesn't even show up in the Eero app as a connected device. Not sure what the problem is but I'm starting to get very fed up with this whole thing. I've been going back and forth since September. I'd love to get a replacement system. This thing is obviously whacked up.

I've been using a 2013 MacBook Pro with my 1st gen Eero setup (3 nodes) for a year, and it's worked perfectly. I just updated to High Sierra and suddenly it won't connect when waking from sleep unless I'm standing next to the primary Eero node in the office (the one hooked up to the modem). It just keeps searching forever if I'm in my living room or anywhere else. The weird part is that once it does connect, I can walk around the apartment and the signal stays strong wherever I am. I'm on the latest Eero firmware according to the app.