Elastic Scrolling Causes Banding in Mac App
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I've implemented a NSScrollView with vertical elastic scrolling on, but there seems to be an odd banding effect when the elastic scrolling actually happens.

This happens regardless of what scrolls past the edge, be it a WebView or a NSTableView (both of which I have in scrollviews that cause banding when elasticity is turned on).

What could be causing this?

![Banding][1]


  [1]: http://i.stack.imgur.com/Yd861.png