i had a customer that had a similar problem. heres what i found. the part of the shift shaft that turns the shift star got turned sideways in the star. this fix was simple, just pulled it out and put it back. so far it hasnt done it since then. almost 6 months. make sure your shaft doesnt have a lot of play in and out. there is a stop on the clutch cover that helps hold it in place. it could have come off the star enough to not catch it.