The Valdensians preached and celebrated the Lord's Supper in the native tongue of the people, not in Latin. However, every source I've read about their customs focus on what was spoken, while I also want to know what they sang.
Do we have any sources that describe their songs, when and how they were sung or indeed if they did sing during their worship services at all?
Of course this question is about the oldest era of the Valdensian movement, way before it merged with Calvinistic Protestantism.