"Left tackle Joe Staley knows the eardrum-rattling peril that awaits the 49ers in Saturday's visit to Seattle's CenturyLink Field.

"It's the loudest stadium in the NFL, so it's very difficult to play there," Staley said Wednesday. "It so loud, and you can't hear anything. Huge home-field advantage."

No stadium has had more false-start penalties by opponents since 2005 (110 in 55 games). The 49ers had only one such penalty in last season's opener in Seattle but still fell 31-6.

"It's a unique environment going up there," 49ers quarterback Alex Smith said. "Obviously we play there every year, but it's still something ... another thing we're going to have to overcome.""