TS-4100 I2S Audio
The i.MX6ul includes an I2S bus. Under Linux this normally connects to a compatible audio codec like the SGTL5000 to provide audio support. See the TS-TPC-8390 schematic sheet 5 and dtb as an example.
Under Linux this is compatible with alsa/pulseaudio, and more commonly accessed by application developers using apis like gstreamer.