Famicom background noise

[Acavamen]

I'm working on a mod for the Famicom using an ESP32 Lite V1.0.0 board. Everything is working fine: the PS4 controller connects and operates as expected. However, there is an unwanted background noise. This noise disappears when I use a separate power supply for the ESP32. What could be the cause of this issue?

In the photo is the board that I am using.
https://ae04.alicdn.com/kf/Sae85e568fb124c5fa3a7b5f92a3a6622G.jpg_640x640.jpg

The video shows what the sound is like.
https://www.youtube.com/watch?v=6I7GOHxak5M

[darthcloud]

You're ESP32 is likely drawing more power than your famicom can handle. Using seprated power for ESP32 sound like a good solution.