If you're feeding F/T, how are you thawing? How do you determine when the F/T is ready? If you do just a quick warmup (for example, with a blowdryer), you can heat up the outside, but the inside can still be too cold (esp the head). The head takes longer to thaw. If you squish the belly gently, you may find that it's a little cold/slushy, too.