The FTC sent letters to the fast-food chain over the summer regarding what was going on with their machines, according to the WSJ.
Franchise owners reportedly complained the ice cream machines are "complicated" and that fixing them when they break is "hard."
"The machines require a nightly automated heat-cleaning cycle that can last up to four hours to destroy bacteria. The cleaning cycle can fail, making the machines unusable until a repair technician can get them going again, owners say," reported the WSJ.
The WSJ said McDonald's claimed to understand customer frustrations. They noted that they have devoted a team to solving the issue.
Many late-night TV hosts, from Jimmy Fallon to Steven Colbert, have made jokes about the problem
Fast-food rivals such as Burger King and Wendy's have even taken advantage of the situation and taken their own shots at McDonald's over the broken ice cream machines.