Razor Mamba Elite Scroll Wheel is Erratic

I have a Razor Mamba Elite and the scroll wheel works, but there is no rhyme or reason for how it behaves. I use the mouse for simple scrolling up and down through documents or on the web. Drawing the wheel towards me, sometimes scrolls down, more often than not, it will bounce back up. Scrolling up causes it to react in a similar way. Something you can spin that wheel a lot of it does nothing. Other times it shots up or down. It's so unpredictable, it is at the point where borders on useless. It's never worked well, but the problem seems to be getting worse. I have not cleaned it with any liquid, I have not spilled anything on it. I have checked the settings. I am at a total loss what to do, except buy another mouse and toss this in the trash.