BUG? plugin size in html5 is incorrect

I have a simple plugin - read from png image. The plugin has correct size when I view in Flash but not correct (larger) in html5. Even when I specify the size directly width="209" height="34" the plugin is larger when viewed in html5.

specs: Windows 7, IE10, krpano 1.17

<plugin name="ms_button"
url="skin/ms_on.png"
visible="true"
width="209" height="34"
/>

Problem solved. It was related to IE zoom. I usually have the zoom set to 125%. I captured an image of a combo box (at 125%) and based the image of a button on the combobox image. Then the button was always larger than the combobox. Thanks Klaus.