My 1st M&T was their greatest hits, even then I knew there was a difference in the female voice on some of the tracks..But after doing some research.on Tammi I just thought it was because of her declining health. If Tammi only was able to sing a line or 2 at a time, as Valerie has said did happen, then of course it would effect the sound of the performance..in some instances on You're All I Need, I hear the Easy Tammi voice on the title track! But there are parts on YAINTGB where MG says Tammi's name. Pretty confusing to me