Diving me nuts as well. I purchased a pair of Shimano SM087 Mt. shoes last season, hoping the stiffer sole would help eliminate hot spots.

While the hot spots somewhat got better, the shoes started squeaking after a seasons use. With any of 3 different Shimano SPD pedals. I lube the top and springs of the pedal as often as I can remember and sometimes get thru a 3 hr ride with no noise and sometimes not. The ***** is, the shoes fit really well and I have 4E feet, but I never had the problem with my older Diadora shoes nor with my Diadora winter shoes.

As a result of the hotspot not really improving as I had hoped, I may shortly be investing in Shimano 105 level road SPD's and a new pair of shoes, under the theory that a wider cleat and platform will help maybe reduce the hotspots as well as the squeaking.

And FWIW, it's not a cleat alignment issue as these cleats are setup identical to other shoes. I also just yesterday replaced the cleats. Squeaked all morning on today's ride