The Auto-Join Annoyance
macOS is designed to keep you seamlessly connected to the internet. If you use your MacBook in multiple locations (home, a coffee shop, the office), the system remembers every Wi-Fi network you successfully join. By default, the “Auto-Join” feature is enabled for all these saved networks. The problem arises when you are in an area where your preferred, strong network (like your home 5GHz band) overlaps with a weaker, saved network (like your neighbor’s guest network or a generic Xfinity hotspot you used once). macOS might automatically drop your strong connection and switch to the weaker one simply because it detected it first upon waking from sleep, resulting in a sudden, frustrating drop in internet speed.
Managing Wi-Fi Network Priorities
To maintain a stable connection to your preferred router and stop macOS from automatically switching to weaker, secondary Wi-Fi networks in your vicinity, you must disable the auto-join feature for those specific access points.
Open System Settings (click the Apple logo in the top-left corner). In the left-hand sidebar, click on Wi-Fi. Scroll down to the bottom of the main window and click the Advanced… button. You will see a list of “Known Networks.” Find the specific network name (SSID) that your Mac keeps incorrectly switching to. Click the circle with three dots (the More icon) next to that network’s name. In the drop-down menu, uncheck the option for Auto-Join. Alternatively, you can completely forget the network by clicking “Remove From List.” Your Mac will no longer attempt to silently connect to this network in the background, forcing it to stick with your primary, preferred connection.