I tried to reproduce your issue by creating a sample page, with an RadAjaxManager which updates the RadHtmlChart every second but I wasn't able to reproduce the issue - I didn't encounter any blinking problems. What you could do in this case is try to resolve the problem by disabling the RadHtmlChart's rendering animations by taking advantage of the Transitions property
Could you try this approach and inform me if it is applicable in your case? If your scenario is different, could you prepare a sample page, which reproduces the problem and send it to me? Could you also specify if you get the same blinking issue on a specific browser (or version) or this behavior is the same for all browser?
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