The STM is dealing with a new hiccup on its new Azur metro trains.
If you've been wondering what could be holding up the metros or why the doors haven't been opening or closing as smoothly as they should, the answer lies at the bottom of your winter boots.
Winter abrasives - those little pebbles and rocks - are jamming the doors.
Commuters track them onto the trains and they get stuck in the path of the sliding doors preventing them from opening and closing properly.
The STM tells CJAD 800 News in an email that it's a bigger problem now than it was last winter because of the major snowfalls this year: more snow means there have been more abrasives being spread and they get into the metro with all the commuters every day.
The STM said it's working on a solution with the Bombardier-Alstom Consortium that built the trains.
The trains are still under guarantee - any corrections won't cost the STM extra.
There are no stats on how many times the metros have been delayed because of this problem.