I purchased the Justboom Zero Dac to go onto the Pi Zero W then use the DAC line out into a small hybrid tube headphone amp all in the same enclosure. The amount of noise from the Pi is atrocious with the headphone out and I'm picking it up on the line out once into the amplifier. The headphone amp is silent when connected to a CDP. Soon as the Pi turns off the clicking, popping stops. Sounds like CPU noise. I'm trying to run headless using my phone to stream from. I tried with a 3B+ and the Justboom DAC as well with no change. Tried separating the Justboom Zero Dac from the Pi Zero with two extension headers (about 1.5") just to see if space would make a difference. Nope. I was really hoping to get all of this into a single small case for my work desk. The Zero was just the right size. I'm going to try using an IQaudio Dac + on the 3B tonight and see if it's the DAC or the amp picking up noise. I did find several threads on a Google search where others had the same problem with the Justboom.
I have a small LM317 linear regulator for the amp, a buck converter to a ATXRaspi power controller PCB into the Raspi. All powered by a single 30V/2.2A switching power adapter.
I have a small LM317 linear regulator for the amp, a buck converter to a ATXRaspi power controller PCB into the Raspi. All powered by a single 30V/2.2A switching power adapter.
