"Can't be that good," is what Tiafoe yelled out but apparently it was! The couple was doing their coupling thing with the windows open in an apartment across the lake. They were having so much fun that the players, the audience, and even the commentators had to make mention of their "noises." 

The mom telling her son to cover his ears is definitely one of my favorite parts of this video. Initially commentator Mike Cation thought the noises were coming from a spectator's phone, but nope. It was the real thing and in real time.