I was setting up my AV system in a new room. Yamaha receiver with Boston Accoustic 5.1 bookshelf speakers. I was wall mounting a the surround Right and dropped it. The pegs holding the face (not the cover) onto the speaker body broke. The next morning I Gorilla glued it back together. That evening I tried the speakers and I had a crackling from the speaker so I went online and ordered a set of Polk S15 as replacements. I used everything in 2 CH setting for a few days. Tonight I switched back to 5CH and had no crackling from the speaker. Either the volume was too low tonight or the first time I tried the glue was not set and I was getting vibration. My thought was to use the S15 as fronts and 2 of good BA spkrs as surround. Any suggestions?