After changing the head I noticed I've got leakage between the rubber grommet and the top cap. The catch area of the top cap that the drip tip slides into keeps filling up with juice unless I keep it completely upright. Have messed with the top cap several times and can't seem to stop the leak. And when I say leak I mean " mouthful of juice after about an hour". Haven't had this problem before. Has anyone else had a similar experience? It's a Vision so I expected it to be better than this.