I need help. My kenetreks kill my feet and not because of heel slippage that you hear horror stories about. They fit my feet perfectly and are very comfortable for short periods of time but about halfway into a day of hiking they start to make the balls of my feet sore just below my big toe and it progressively get worse until it hurts to walk by the time I make it back to the trailhead. I need suggestions on how to fix this and I don't want to hear get different boots. Any insole recommendations, lacing techniques, etc... would be appreciated. They're mountain extreme 400s