fastflight string with the new heavy serving

[Masboy]

I got new fastflight with the new heavy serving on it and it was off center about 3/8 inch and had a lot more twist in the short side of the serving. when I put it on and was shooting my arrows seemed too fly ok for a while then as I had too put a few twist in it my arrows started to fish tail . so I took off the heavy serving and reserved with 026 angel and centered my serving and my arrows flew like darts? I never had that happen before when I had some servings that were off center. do you think the thicker serving off center, more twist on one side,or a little of both?