When you use an audio interface, there are things to keep in mind to make sure it works. If you connect the interface incorrectly, Yousician won't recognize it.
As an example, you should connect headphones to the interface. Ensure that you connect the headphones before you connect the interface to your device.
After you connect your instrument, you might need to change the input device. You can change it via the Advanced audio settings from the Game tab.
With your instrument connected, adjust the Mixer volume from the Pause menu to hear yourself play.
There are lots of audio interfaces available, and the right one for you depends on the device(s) you’re plugging into. Check out the following videos to see some options.