How do I keep two objects using Sine in sync?

Quick question....

I've got a sprite onscreen that uses a sine movement to make it bob up and down.

I wanted to overlay another sprite that acts like a pattern or design over the first sprite. I've set the sine movement to exactly the same parameters as the first and used an overlay effect on a higher layer but it keeps going out of sync.

Is there something I'm missing? Any suggestions on what I should be keeping in mind?

Cheers

Make sure all of the random modifiers are at 0

(period random, period offset random, and magnitude random) these will add a random value based on the number entered to give each sine a slight difference.

pattern.Y≠sprite.Y ...set pattern.Y =sprite.Y

What about using the "Pin" behavior?

Thanks for the tips, guys.

Yeah, I'm using the Pin Behaviour and I'm 90% sure all the random modifiers are at 0.

I originally thought slight differences in sprite 1 and 2s collision boxes was throwing the sync out but I noticed it would just go out on its own free will from time to time.

Try and turn collisions off for pattern