Andy Murray claimed playing at the US Open during a downpour was like playing with headphones on.

The Scot progressed to the third round of the New York Grand Slam with a 6-4, 6-1, 6-4 win over Marcelo Granollers, but the victory wasn't without complications.

The match was played under Arthur Ashe Stadium's new roof, which amplified a downpour midway through the second set.

Both players stopped play momentarily, with neither certain of what was causing the noise.

"It's more difficult because we use our ears when we play," Murray said.

"It's not just the eyes. It helps us pick up the speed of the ball, the spin that's on the ball, how hard someone's hitting it.

"If we played with our ears covered or with headphones on, it would be a big advantage if your opponent wasn't wearing them.

"It's tricky. You can still do it but it's harder, for sure."

The new $150 million roof has already caused problems for players at this year's US Open, with several complaining of the way it amplifies chatter from the notoriously noisy New York crowd.

Rafael Nadal admitted after his win on Wednesday night that the noise was "a little bit too much during points," but Murray believes players will adapt.

"The players will deal with it. You get used to stuff," the Scot said.

"As an athlete, that's what you do. We adjust to different conditions every week. Playing in the day to playing in the night is totally different from one day to the next.

"We change balls. I played the Olympics with one ball, Cincinnati with a different one, a different ball again here.

"We change stuff all of the time, but it takes time to adjust and then get used to that. I think that's why everyone is talking about it now, because it's something new.

"I'm sure if the feedback is that the TV or spectators aren't enjoying the match as much then they will look into it and try to change it.

"But what I have heard it is fine on TV, I don't know what the fans have said about it yet but the players will adjust."