Bluetooth and Wi-Fi fight over 2.4GHz

I have a phone running a Snapcast client: it pulls synced audio over Wi-Fi and plays it out to a pair of Bluetooth headphones. It buffered constantly: a few seconds of audio, then a stall, then a reconnect. The Wi-Fi signal was excellent (RSSI -44), the server was idle, and the same stream played fine elsewhere, so naturally I blamed everything except the obvious thing. Eventually I just pinged…