I have a very simple setup: Bela connected to two speakers from the amp outputs running a SuperCollider patch that simply connects the audio inputs to the outputs.
When I use my 5v (2250mA) power supply, there is a lot of noise. But if I also connect Bela using the USB cable to my laptop (connected to its own power supply), the noise disappears.
I've read the many threads on noise issues here but couldn't figure out any that had a similar issue with such a simple setup. Maybe the power supply I'm using is the source of the problem? I find it very strange the the noise disappears if I add the laptop (when connected to power)...