The Signal Strength Shuffle
macOS is designed to keep you connected to the internet at all times. If you have previously connected to multiple Wi-Fi networks in your area (for example, your home 5GHz network, your home 2.4GHz network, and perhaps a neighbor’s guest network), macOS remembers the passwords for all of them. By default, if the signal strength of your current connection drops slightly—perhaps because you walked into the kitchen—macOS might automatically disconnect you from your preferred 5GHz network and switch you to the stronger 2.4GHz network. While this maintains a connection, it often interrupts active downloads, drops Zoom calls for a few seconds, and can leave you stranded on a much slower band without you realizing it.
Prioritizing Your Preferred Network
To maintain a stable, uninterrupted connection and stop macOS from automatically switching between known Wi-Fi networks based on fluctuating signal strength, you must adjust the auto-join settings for each network.
Open System Settings by clicking the Apple logo in the top-left corner of the screen. In the left-hand navigation pane, click on Wi-Fi. Scroll down the main window until you see the section labeled Known Networks (you may need to click an “Advanced…” button at the bottom to see the full list on older versions of macOS). This list displays every network your Mac has ever joined. Find the secondary networks that you do not want your Mac to automatically connect to (like the 2.4GHz band or the guest network). Click the three dots (More icon) next to the network name and select Network Settings. Look for the toggle switch labeled Auto-Join. Click the toggle to switch it to the Off position. Repeat this for all secondary networks. Your Mac will now only connect to your preferred network and will stubbornly hold onto it even if the signal drops.