I have an Energy Take 5 speaker system and use Energy's speaker stands. However, on the top of each speaker stand (where each speaker sits) is pentagonal piece of plastic that has been glued to the stand. It sits in between the bottom of the speaker and the stand itself. The screws that bind the speaker to the speaker stand all fit fine. My question is, "What are these pieces of plastic?" What do they do? Are they suppose to be there? Thanks!