UPDATE: Just awhile ago I took off the wheel to inspect the cassette and noticed on the smallest cog that two of the tooth were rubbing on chain more than the others. Two of them were cleaner than the others so it seems like they are miss aligned. I will to replace the 11t cog with a new one and see what happens. My only concern is that I buy most of my stuff from ebay and i don't want to buy the wrong part.