BorgeStrand writes: The Audio Widget project has resulted in a fully functional open source USB digital-to-analog converter. The project firmware implements asynchronous USB Audio Class 1 & 2 in an Atmel MCU. Because of its recent popularity, one of the hardware implementations was subjected to CE and FCC test regimes. And it passed with flying colors. The AB-1.2 DAC from QNKTC (Quantization Noise Killed The Cat — www.qnktc.com) has firmware, electrical schematics and a Windows ASIO driver which are all open source. Although it plays well out of the box, anyone so inclined is very welcome to modify its internals and share their results with the rest of the group.