4.5 stars
On my C2+Android, with my 3rd party speakers, using a usb sound dongle or my LCD's audio out, i would get terrible hiss. Loud like a CPU fan. I tried everything from chokes to a regulated PC power supply, still hiss.
Using the Stereo Boom Bonnet with my speakers solved the hiss problem 100%. I have to turn the Bonnet's volume to 100%, the C2's volume to 100% and I can only just barely hear any hiss from my speakers.. With my ears pressed against the speakers.
The reason I'd be rating this at 4.5* and not 5 if i could, is because the included speakers aren't very loud. Even at max volume they are fairly quiet, at least for my C2 using android. Might be better in linux.
So you should arrange for different speakers. Though i wish it had solder pads for the speakers, since the included connectors are pretty small. And the lineout headder appear to be before the amp.
But for the price, this is great, definitely beats ebay PCM5102 boards as this one includes an audio amp as well.
