I just purchased and installed Insinkerstor Evolution SelectPlus. Very quiet, easy to install. But when try to use it, the drain won't drain, or drains slowly. I have to stick something in the rubber drain baffle (not safe) to get it to drain. I would think for the price tgat it would be engineered better, safer, etc. How can I fix it? I'm thinking of cutting a big chunk out of it, help.