[aigel]

Do you really still have a 3000 mile chain on there? I take good care of my chains, but none of them last past 2500 miles without stretching past wear limit. 1500 on the MTB. I toss them when they are over 0.75. Try a new chain and size it from scratch like you will see in those video instructions. A stretched chain will absolutely ride high and not seat all the way in the teeth and be more prone to hop off. By the way, that chain is probably less than 10 bucks.