I have tried the basic setup from this demo
and thing seemed to work fine on my end and no errors were thrown. I am attaching here my test page so you can compare them with your and try to find the difference that causes the problem.
I can also suggest making sure that you are using the latest version of the controls (Q2 2013 SP1 at the time of writing) to see if this resolves the case.
You can also try removing browser plugins/addons to see if any of them is the reason for the problem.
On attaching a project - this can be done in support tickets, but if you post the needed modifications on my sample here, along with a list of steps I need to take to reproduce them we can start investigating the case. Recording a short video of your scenario can also help us see how the problem occurs. If there is a live URL we can examine the problem it may also help.
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