I think I have finally figured out this time when I originally put new belts on deck the belt was a little thicker than original and it seemed a bit tight. Well I figured it was wrong so I got another belt thinner and a bit longer. That seemed to work. Well with all the BS with the warbly I started focusing elsewhere. I tried lots and switching parts. Well I have finally for the deck sounding great, no warble that's the beautiful thing when you have 2 decks to make a perfect deck. I finally accomplished that