“Greatest Hits--Live.” Frankie Valli and the Four Seasons. Priority. Almost nothing is right with this CD, recorded at a 1980 reunion concert in New Jersey. The accompaniment is amateurish. The mix is inconsistent. Most often the sound is hollow and tinny. The vocal harmonies are frequently ragged and Valli’s voice, no longer as potent in high register, occasionally drifts off key. Nearly all of this CD is devoted to lukewarm versions of oldies like “Sherry,” “Let’s Hang On” and “Swearin’ to God.” If you’re feeling nostalgic for the Four Seasons’ sound, skip this one. It may ruin any fond memories you have of this group.