Hey guys, Lately my samsung ht-z310 hts is experiencing some sound issues. After about 10-15 minutes of playback on any mode (radio, dvd, xbox) the sound just seems to turn itself down. It then becomes muffled and is barely audible even on max volume. Speaker wires seem fine and all plugged in, I should say it plays at normal volume for those first few minutes also. Thanks for any help.