Using the Volume Control plugin

Yeah, I had that problem, too. What I did for mine was I created the menu first, then right clicked inside the <empty> menu and selected the plugins from there. I had a problem with the width of the volume controls, too. It seems the width is only determined the very first time the bar is created, and fills as much width as available. If your menu is otherwise empty, the bar is very narrow and won't resize if you add something wider to the menu. So what I did to get around this was add the winamp control plugin first, as it has a fixed width, then added all the volume bars. This made everything the same width. Hope this helps!