Seattle: notoriously loud.

For N.F.L., Crowd Noise Has Become a Headache - New York Times:

The noise issue came to the forefront as the Giants prepared for today’s game against the Seahawks at Qwest Field, the notoriously loud stadium in Seattle. When the teams played there last November, the Giants were called for 11 false-start penalties, the kind often caused by a failure to communicate. The Giants had 16 penalties over all, the highest number for the franchise since 1949, and lost in overtime, 24-21.

Go figure. The league is considering letting visiting teams use walky-talkies. Giants have sensitive ears. Poor Giants.