I have faced a very very annoying problem with my SPD shoes, and it happens on two pairs of shoes from different manufacturers (Shimano SH-AM7 and Northwave Outcross 2 Plus). The problem is a very bad squeaky sound on every pedal stroke (on the pushing phase of the pedaling, when pulling it is quiet)
Well, to begin with, all shoes have similar construction. On the sole of a shoe, where the SPD cleat is bolted, there are basically two large holes. Manufacturer usually covers it with transparent film on the inside of the shoe. But this film adhesive is so weak it usually gets totally gone after you wash your shoes couple of times. So what I do -- I put regular duck tape inside my show to cover the holes.
But after I do that -- this super ennoying squeaky sound appears which happens on every pedal push (in Shimano case, Nortwhave makes this sound even without duck tape) I have tried lots of solutions. Like making holes in the duck tape, so that there is better air flow (doesn't help), I have wd-40-ed the pedal spring, thought it was the problem. But it is definetely the shoe, because when I pedal without being clipped in there is no sound. I have removed the duck tape at all from my Northwave shoes, and the sound is still there! So it could be the insoles rubbing against the metal cleat hanger.
The only solution that worked for my Shimano shoes which I used a year ago, it was completely sealing the holes with silicon sealant used in plumbing. But it is a nightmare to remove it in case you'll have to. But I haven't silicone sealed my Northwave yet, trying to find a better solution.
I just don't understand why manufacturers of the shoes make this terrible flaw in the consctruction. And since there are no thousands of squeaky shoes riders out there, it seems that there is some solution I don't know of.
Thank you for any help in advance.