It would be hard to reproduce the problem without the full content of your page. Could you please send us your markup and CSS or a page in which the problem can be replicated? I suppose that somewhere you have set position relative for the MasterTableView. If this is the case please try setting:
Also if you are using static headers and the width of the column is being set please remove the width from one of the columns so the grid can recalculate the alignment. In attachments you can find the project in which I have tried to reproduce the described issue.
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