I am sorry to hear you are experiencing this issue. It seems this is something specific for the application you are testing. The only way I can think of we can investigate this issue is to provide us with access to your application so we can analyze further. Please note that you are now typing in a public accessible forum so if you are going to share private information you will need to open a support ticket. It would be great if you provide access with a working test and instructions on how to repro.
Thank you for your understanding.
the Telerik team