by Stephen Thomas Erlewine 　　  　　Three albums in and Lifehouse sound comfortable -- comfortable in their skin, comfortable working within the constraints of adult alternative radio, comfortable enough to deaden any possible lingering Creed or Stone Temple Pilots comparisons that might have plagued them after their first two records. Here, on their eponymous third album, Lifehouse is a rock band that doesn't rock. They strum acoustic guitars and sing earnest mid-tempo anthems and ballads, all given a slick shine by producer John Alagia, who has previously worked on records by the Dave Matthews Band, John Mayer, and Jason Mraz -- a collaborator whose very presence indicates how far the group has shifted from its early Brendan O'Brien productions. While some longtime fans will miss the band's harder side, Lifehouse sound, well, more comfortable in this setting, and they've made an album that's smooth, mellow, reasonably tuneful, inoffensive, and thoroughly unmemorable. It's not an album that makes waves, it's a record that's designed to ease onto the AAA radio waves, where it will politely sit next to songs by Matthews, Mayer, and Mraz. And on that level, Lifehouse is indeed a success, since it's pleasant enough as it's playing, but the drawback is that it could too easily be mistaken as the work of many other bands who mine the same territory.