I am testing a Pi 2 with a WiFi dongle and a UCA202 DAC in my boat. I have tried two USB power sources in the boat. One is a Chinese USB power supply, the other is a Blue Seas USB outlet. Using either I had a high pitched tone and could hear noises from the Pi through the speakers. I do not have any noise if I use my MacBook to power the Pi. The DAC and WiFi are powered by the Pi.
So I believe I need a cleaner 5 volt power supply from the boats 12 volts. I am considering using a UBEC.
What do you recommend?
