e-revo having some issues

The slipper is new. I have two, one that came used on my roller, and one that was on a new tranny I bought. I'm using the new one at the moment, so no use on it at all.

I'm more concerned with the slipper than the motor mount at present. I'm sure with loctite and some sort of washer I can prevent it from moving, but this stupid slipper, sheesh. I literally have to tighten it every few minutes during running. I've run it just about as tight as I can get it, which I don't like as it doesn't slip at all under stress. At least, not until it comes loose and does nothing but slip.