Hello! I have an AIWA stereo integrated amplifier 8700 and the problem with it is that when i listen to music or any other sound after a while the sound drops but you can still hear a weak sound though, I can turn it back to normal only when i turn the volume up to the maximum, i can hear a cracking noise then the sound is back to normal, but I have already blown up 2 pair of speakers. The sound drops often and i'm afraid to blow up some more speakers. Please Help!