I need help identifying the issue with my Ford Fusion horn.

I have a 2016 Ford Fusion and there something wrong with my horn. Half of the time is sounds broken. Every time I take it to the dealership (since it's under warranty) it sounds perfectly fine. I just need help finding the problem and what's causing it. I'll link a video in the description of my dashcam recording the horn. via /r/cars http://ift.tt/2u5YyTX