You use the cheap foam roll up to fit in your ear type and shave small slivers off and use one the right size/shape in near the offending tab/seam/gap and put the back on. The sliver of foam will form fit into the tab/seam/gap that is creaking and stop the noise. Not sure how off topic that is but it is a DIY fix.
The trick is finding the two points of contact that are rubbing and making the creak sound and getting the foam between them.