Review on Audio Injector Zero Sound Raspberry by Chris Hernandez

This works great once everything is set up. It's as simple as soldering a header (which is NOT included!), plugging it into the RPi's GPIO port, and configuring a few lines in the /boot/config.txt file. Unlike other pssoters, the AudioInjector website has plenty of support! Sounds a lot better than the original built-in audio on the Pi. I didn't get a chance to try out the input options. This is an oversampling DAC using the WM 8731 chip.