I have the same problem with my Boulder. I tried socks made of thin cotton, thicker cotton, 2 different kind of wool with the same result. It would be quicker to cut the socks than take them off. Last Thursday I went for a ride, it was quite hot, but this time I whore Jitsie trials socks, I won't say there cool but I felt better in them. I will try to find what they are made of and try to find a short version of them.
Guy