Laggy ugui scrollview

I have been commented from my customer about laggy scrollview when scroll up down compare with other application. It is happen all device (ios, android). I have tried to find forum about this problem and followed comment and these are what I did.

1. not use rich text in UIText.
2. no check pixel perfect in Canvas.
3. try to not use transparent (still have little bit).

It is still lag for scrollview movement. I have tried to create empty project and create only scroll view and some button text, scollview also still look laggy.

I uploaded a sample video in youtube

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Does anybody have an idea? What did I miss?

 

I think this is the problem of uGUI, I switched back to NGUI lately and the scrollview became sooo smooth.