According to the editor of Luther’s works (English),
After October 13, 1521, masses were no longer celebrated in the Augustinian monastery at Wittenberg; on October 17, Karlstadt presided at a disputation where it was, proposed that all masses be abolished. On other occasions he expressed himself about images, etc., in such phrases as: “Organs belong only to theatrical exhibitions and princes’ palaces”; “Images in churches are wrong”; “Painted idols standing on altars are even more harmful and devilish.”
He wasn’t wrong. But those remarks didn’t calm things down. On the contrary-
The impact of such ideas and sentiments upon a student body and a populace which had seen their famous professor publicly burn the volumes of canon law and even the papal bull which excommunicated him, inevitably led to demonstrations, some hilarious, others destructive. On October 5 and 6, 1521, a crowd of students jeered and threatened a monk of St. Anthony who had come to Wittenberg to collect alms for his order. On November 12, the prior of the Augustinian cloister complained to the elector that some monks who had left the cloister had joined forces with citizens and students to stir up trouble for the monks who remained faithful, and that he himself hesitated to appear on the street for fear of being attacked.
Reports of extreme measures and consequent unrest in Wittenberg gave Luther such concern that he determined to pay a secret visit to Wittenberg in his assumed character of “Junker Georg,” wearing a beard and the trappings of a knight. Traveling by way of Leipzig, he arrived in Wittenberg on December 4, 1521, lodging at the home of his colleague, Amsdorf, where he was able to confer with a few of his most intimate friends. After a stay of three days, when rumors of his presence began to spread, he departed as quietly as he had come, reaching the Wartburg by December 11.
I like Karlstadt. Sure, he went crazy eventually and joined the 16th century equivalent of the Montanists (Pentebabbleists), but early on, like Tertullian, he was super fun.