I had this intermittently shortly after purchasing 1 year ago. One day it would not start. Replaced starter. Now, rarely it does the clunk thing. Starts right way after. It may seem crazy but it seems like if you don't just roll through the whole starting thing or get interrupted, then it happens (based on my experience). It was like an older car I had where you had to hit the solonoid with something hard to get it to move to a good spot. But I don't know anything. Other times it is like a computer issue where it's like the computer needs to reset itself.