I am building a MIDI controller/Launchpad with a Teensy 4.1 and I would like some guidance on developing a code to read WAV files from an SD card and output the audio. I already developed the MIDI part of my code and it works, but I am also planning on using it as a standalone device, feeding the Teensy from the 5v pin and displaying a folder menu on my LCD screen to select an audio library and assign different WAV files to the buttons of the Launchpad. I need help understanding the necessary functions to 1) output audio from the Teensy 4.1 (S/PDIF seems to be the audio port). 2) Reading and selecting WAV files from the micro SD card the Teensy will be reading from it's slot 3) Separate MIDI from standalone (I understand the MCU can be set to serial+MIDI+audio). Thank you in advance