Thank you for your feedback.
This appears to be a known issue. You can find it and vote for it here
in our Telerik Feedback Portal.
I am sending you a demo pages set. When you move or resize RadWindow, the audio tag disappears. Audio does not stop playing, however.
If Behaviors="None" is set (<telerik:RadWindowManager ID="RadWindowManager1" runat="server" ReloadOnShow="true" Behaviors="None"></telerik:RadWindowManager>), then the audio element does not disappear because the RadWIndow cannot be moved or resized.
You may try to use Content Template instead of a simple page for RadWindow. You can find how to set it in the RadWindow - Content Template demo
. I hope this can solve your issue.
If the issue reproducible in the demo pages I send you is not the one that you've experienced, do not hesitate to contact us again. In order to be able to further isolate the issue, please specify the RadControls Version you use. Providing a sample page where your issue is replicated would be highly appreciated. You could use my sample as base and post the changes that need to be made, and the steps that lead to the problem.
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