Do you have an electric guitar? You can use your Speaker Cube as a guitar amp.
This feature requires the Speaker Cube to have firmware version 1.0.9 or later and an audio cable to connect your guitar to the 3.5 mm AUX input on the Speaker Cube. This cable typically has a 3.5 mm plug on one end and ¼ inch on the other. Connect the cable from the guitar to the speaker, power on the speaker and follow these steps: