If you're looking for the Audio Adapter+ for Analog Discovery 3, check out its resource center, here: Audio Adapter+
The Analog Discovery Audio Adapter is a module that allows analyzing audio signals from external sources or from the Analog Discovery audio jack socket. It is equipped with a Mono and a Mono/Stereo Jack connector that are connected to the inputs of the oscilloscope. The Audio Adapter is equipped with the 2×15 Analog Discovery connector, which makes it compatible with Analog Discovery Legacy and Analog Discovery 2. An additional 2×15 Analog Discovery connector is loaded as a pass through for the digital signals that can be further used for other applications.