Opened them up recently for another issue and along with a lot of dust this is what I found.[frame]
This was the only shoe that looked cracked but I have a suspicion it was the one doing the lions share of the work too as most of the front cylinders are very stiff.[frame]
We are going to replace the lot and use Mintex shoes now so I wont know if it was the dust or the cracking that caused the brake squeal.