Non-Wi-Fi signals (like those from microwaves, Bluetooth devices, cordless phones, garage door openers, baby monitors, etc.) can all congest a channel but may not show up in a scan. Channel scanning apps don’t always measure other sources of congestion and interference.A single Wi-Fi network with heavy use can clog a channel far worse than many unused networks.
If you've noticed that your Google Nest Wifi or Google Wifi network is sharing a channel with several other networks, don’t worry.
