sedan soft top flutter

I just got my sedan on the road . No interior yet. I have a new top on that I did myself following the manufacturers instructions.
Foam rubber , I think 3/16's" laid over wood slats(31chevy)and vynle over that tacked around egdges. with a vynle border tacked around the edge . Looks good.
My question or problem is it flutter a little when driving. I have only had it up 35mph. Am afraid of losing the top.
Will this go away after I install sound isulation like dynomat. I plane on doing that. The top is not glued or anything like that.
What has been your experience. Thanks in advance for any help. Bob.:D