If Grammys were given for best whispered album of the year, the Bee Gees’ baby brother would have this year’s award locked up. Unless you intend to mail-order (form attached) an Andy Gibb poster, T-shirt or nightshirt, this LP, his first in 18 months, will be a disappointment. Too bad. The high points are harmonies with the three older Gibbs (Desire) and a pair of duets with Olivia Newton-John (Rest Your Love on Me, I Can’t Help It). The low points are too common lyrics like “Wherever you go/You live/Inside of me/I was born to make you see.” Still, this is a clean, slick pop sound; Barry Gibb co-produced with two of the Bee Gees’ Miami studio whizzes, producer Alhby Galuten and engineer Karl Richardson. And there is the attractive Gibb sound of melting chords and quivering sincerity. Trouble is, Andy lolls the drowsy pace that makes After Dark seem to be about sleeping rather than something more stirring.