Connecting bluetooth device slows down wifi

The WiFi channel is set in your WiFi router settings... it's likely set to 'Auto' so it can find the least-used channel. I've found the 'Auto' algorithm in most routers to be buggy... just figure out which channel is least-used over the day, manually set your router to that, and if you start getting too much interference such that you're getting slow speeds or dropped connections, repeat the process with another channel.

If you're in the US, you'll find that Verizon WiFi tends to completely swamp the higher channel numbers, and people who don't configure their WiFi out of the box other than setting the SSID and passphrase tend to swamp the lower channels, so I run channels 4 - 8 (channel bonding to increase throughput).

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