POP MUSIC REVIEW : CS&N; Takes Its Deja Vu Credo Too Far : Icons of the ‘60s have some good moments at Irvine Meadows, but their musical past haunts them, perhaps limiting their talents.

“We have all been here before. . . . We have all been here before.” That refrain from Crosby, Stills & Nash’s “Deja Vu” pretty much set the tone of their 2 1/2-hour show at Irvine Meadows Amphitheatre on Sunday. While highly musical and, at times, even lively, their performance also showed why the ‘60s icons are an ideal sponsor band for VH-1, the retro-video network whose current motto is “For when you’ve seen it all.”

Though they waited until the second half of the show before plunging into the hallowed harmonies of their 1969 debut album, “Crosby, Stills and Nash,” a smug stasis overhung much of the proceedings. Several of their contemporaries--with one notable example being old crony Neil Young--continue to make music that challenges and prods, and properly regards art as a lifelong odyssey. But CS&N; seems more akin to self-satisfied lotus eaters who have given up the quest.

Granted, they do some fine grazing. Sunday, their time-worn voices harmonized far better than they did in concert in their glory days (check out the old CS&N; live bootlegs for some really off-key action). And with a fine back-line band pumped by longtime drummer Joe Vitale and David Lindley’s former bassist Jorge Calderon, the music really kicked in places.

One well-placed kick was the opening number, Stephen Stills’ “Love the One You’re With,” which set a lively groove that sadly wasn’t matched by all that followed it. “Wooden Ships,” often a creaky item in past shows, also flew, with keyboardist Mike Finnigan and guitarist Stills exchanging terse instrumental lines. The finest harmony work came on an arrangement of “My Country ‘Tis of Thee.”

The trio offered five songs from the current “Live It Up” album, but only one actually displayed much life. That was “Yours and Mine,” a moving missive about how children are raised to participate in a violent world.

They offered their handful of ‘70s and ‘80s successes, including “Just a Song Before I Go,” “Wasted on the Way,” “Southern Cross” and “Got It Made,” along with several selections form their respective solo careers. Among those were David Crosby’s recent “Drive My Car,” Stills’ “Change Partners” and Graham Nash’s “Cathedral” and “Please Come to Chicago.”

That song’s heady refrain of “We can change the world” seemed sadly at odds with the complacency--admittedly a lovely , well-honed complacency--of much of the performance. Perhaps, given just how the world has changed in the last 20 years, it’s harder to find the spirit to sing such songs.

While the trio and its band did put a surprising enthusiasm into the obligatory “Wooden Ships” and “Suite: Judy Blue Eyes,” some of the “classics” that dominated the show’s second half--such as the encore of the insufferable “Teach Your Children”--had the air of a liturgy that has been repeated into meaninglessness.

Like the Beach Boys and far too many other performers that the VH-1 generation clings to, CS&N; has become an institution, resistant to change or risk. And network slogans or no, as their frighteningly vital pal Young continually demonstrates in his work, just because we may have been alive in the legendary ‘60s, we haven’t yet “seen it all” by a long shot.