Oh boy, outside of the brilliant Zelda, the Nintendo Switch launch has been one marred by a number of little issues. From Joy Con controllers losing sync to dock's scratching screens and more. And now we can add the Switch looking for Wi-Fi networks causing massive frame-drops in games. This is something we've witnessed in person, with the reliably 60fps Fast RMX turned into a stuttering mess inexplicably when showcased out of the home.
According to reports it has to do with the system automatically searching for Wi-Fi networks, causing a massive load to the CPU. Nintendo is aware of the issue, and it should be resolved in an upcoming update. In terms of other issues people are experiencing with their Switch's, Nintendo are investigating and gathering more information before formally announcing any planned fixes.