Brake prob

ok i have a funny noise comming from my rear brakes. it sounds like something is getting hungup then dropping loose. then when i start to come to a stop they squeak. i have checked them out but nothing is loose, all springs are in there spots, and still streatch. they have been doing this for about a week. my last brake job was done last summer, by me. i know its not the front because i just redid them today.

i have a 96
15'' stock rims

thx for the help

Warped drum maybe.
Is there still material left on the shoes?