ESP32 Audible Noise When Using WiFi

I kicked off the build of my ESP32 walkie talkie in the previous video - https://youtu.be/MilQztrItbA and noticed some noise whenever the WiFi was sending data.

My initial reaction was that this was the same problem we've seen before with noise on the power rail as we've seen with Electret microphones - https://youtu.be/pPh3_ciEmzs but checking on the scope it was all fine.

Then someone suggested it was actually audible noise that the ESP32 makes when it sends audio! They've got a video here that shows it - https://www.youtube.com/watch?v=8TX7rivphns and I've managed to capture it myself! ... https://www.youtube.com/watch?v=LCmgfb5HrIY