I basically had the same issue with my new, very expensive Shimanos (the ones that get molded). I switched from Sidis because I needed a wider toe box and a a narrow heel. The first ride was so painful, I had to ride without insoles. I promptly went to the Good Feet store and got the blue insoles. It's better, but basically, I have to barely tighten the ratchet and wear the thinnest socks I can find. I still have issues with my left foot, that has a bunion and is the one I clip in/out with.