I don't know what it is but this place just doesn't do it for me anymore. I always feel like I've had better Korean food elsewhere and the service is less than mediocre. I was feeling little under the weather and decided to get the duck mandoo guuk. I've had it before and it was very tasty but that day it was lukewarm and not enough duck. The food used to be really good but never wow'd me. Now it's just "good" enough to come with a large group of people.