MYRTLE BEACH, S.C. (WBTW) — The Federal Trade Commission is investigating why ice cream machines at McDonald’s restaurants are frequently broken, according to a report from the Wall Street Journal.

WSJ reports the FTC sent letters to McDonald’s franchisees over the summer asking what’s going on with the ice cream machines.

The report says McDonald’s franchise owners have complained about how complicated the machines are and that fixing them when they break is hard.

The FTC wants to learn how suppliers and equipment are reviewed, and if restaurant owners are allowed to work on the machines in their own stores, according to the Wall Street Journal.

The FTC declined to comment to the Wall Street Journal.

A 24-year-old ice cream fan fed up with the frequently broken McDonald’s machines managed to reverse engineer the McDonald’s app to create a map of every broken soft serve machine in the United States.

The map tracks the percentage of restaurants that currently have broken ice cream machines and uses red and green labels to identify stores serving up soft serve.