* * 1/2 THE JETS. "Magic." MCA. The debut album by these seven Polynesian popsters was one of the surprise hits of 1986, spawning three Top 10 singles: "Curiousity," "Crush on You" and "You Got It All." They've been on the road ever since and this album--recorded in no fewer than 12 different studios--sounds as if it was worked on in between concerts. Less-than-enthralling cuts like "When You're Young and in Love" and "The Only Dance" sound like hurry-it-up music designed to meet deadlines, not fans' expectations. Other cuts, like the frisky rockers "I Do You" and "Rocket 2 U," plus the sumptuous ballad "Make It Real," prove how good this group can sound given tunes with a little substance. There are some entertaining moments, one of them being "Cross My Broken Heart," a dance cut from the "Beverly Hills Cop II" score. But this album isn't nearly ambitious enough to showcase such a hard-working group, nor point them on the road to becoming the biggest teen group since the Jackson 5 and New Edition.