I suppose it's a problem produced by your Gavick template. If I search for something with "Firebug" enabled in my Firefox browser, it tells me "$Gavick is not defined
You can try if it helps to disable 'Using the Virtuemart jQuery' in VM2 Configuration - Templates.
If it doesn't solve your problem, I would recommend to try another template for comparision, i.e. the free "ShopLab" template.
From what I frequently see in the forum, I think it generally is a good idea to avoid templates which use their own framework. They often load a lot of things conflicting with VM2.