yes when i went to see the car i thought they'd just need a bit of oil, was searching Strictly Technical last night just going through the pages and came across a post about how it fix it (can't find it today). Basically the belt is rubbing off the trim inside when you pull the belt out, take the trim off, has 1 popper at the rear and just pulls off. inside the trim you will see where the belt is rubbing, there are 3 strengthening tabs which run across the trim, i cut the top 2 down flush and put it all back together, no squeaks
easy jobs takes about 15min per side