Can you please clarify the browsers under which you are testing your page as well as the version of the Telerik controls that you are using? In case you use IE you should note that in general the stacking order in IE6/7 is rather broken
. To fix it, make sure that the container of your image has lower z-index (and position: absolute/relative if needed) than the container of your RadMenu (the containers that are on the same level in the DOM). However, in case this does not help I would suggest that you open a support ticket and send us a simple project or a live URL that demonstrates it?
the Telerik team
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