I have two Taylors I love (814CE and 655 CE), but when I put straps on them to play while standing up, they don't remain balanced around my neck. They both tip immediately down, the headstock pointing towards the floor. I have to exert some pressure at all times to keep them balanced in playing position. Is this normal? Is there something I can do about this? I'm using the factory installed pins and it doesn't matter which strap I use.