I tested the scenario that you describe with the 2013.1.220.40 version of the Telerik controls but I was not able to replicate the issue that you describe. Here
is a short video for your reference that demonstrates what I get from my side. Can you please open a support ticket and provide us with a very simplified runnable project that we can test locally and help you out ? Can you also clarify the version of our controls that you use?
the Telerik team
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