I have a pair of Klipsch 4.5's I purchased years ago. Shortly after purchasing them I noticed some odd noises coming from them during loud passages. I found that the back panel of both speakers was vibrating and were coming apart from the speakers. I haven't used them in a while and I would like to again but I would like to correct this issue. What would be the best way to fix this problem, and is this a common issue with these speakers?