Solved!!! I used a LeCroy USB Mercury T2™ USB 2.0 Protocol Analyzer analyser (borrowed from a friend - owe him a beer) to reveal the XMOS device was not ACKing OUT endpoint packets from the host. Protocol Analyzer analyser Screenshot: https://s9.postimg.cc/pfymcmytn/No_OUT_ACK.jpg I delved around th...

Hi All, I've added a new IN/OUT Interrupt endpoint to the USB Audio Reference design (to send data from the USB host to the I2C port) and am having some issues with it communicating with WinUSB. My driver is from Thesycon (4 in, 8 out) with my custom descriptors added (see below). My design appears ...