Here's a block diagram of what I have. I tried powering the Arylic from a battery to try an avoid ground loop and it fixed the problem, so it's either a ground loop or a poor quality buck convertor - I suspect the latter. Will try some smoothing on the +5V to see if it fixes it. Thanks for your help.
But what you really want is a LT3045 based regulator. But you cant feed that 48V. And you can't set one after an USB block because it needs say 6V to work properly. If you have ambition with this setup you really ned to get a proper power supply for the streamer. But one can't hope for all that much with a complete receiver, controller and DAC for 49 bucks... 
The amp seems really good and in an other league than the Acrylic board. Maybe not the most balanced combo perhaps...
//
The amp seems really good and in an other league than the Acrylic board. Maybe not the most balanced combo perhaps...//
i @
@3eaudio, some class d amps seem to run out of steam when used for subs generating amplifying infasonic (down to 10Hz) how is the performace at this range, as I have not seem many charts. Is there a power drop? and if it is, how much is pex[-ected to drop (in percentage or watts) . Thanks