Using one Turbosound IP1000 compact pa system for my acoustic trio. Sometimes I hearing a "crackling distorted " sound coming from the top array column. I check all of the channel gains and not clipping. The master fader channel is not clipping. EQ , and speaker position make no difference. All of the vocal microphones and instrument channels have the crackling /distorted sound. The audience cannot hear it when everyone is playing but the players can. Checked all of the cables and they are fine. Most venues we do not have the issue. There is a particular venue that we experience it from so we were wondering if there was some type of electrical intereference going on. I have two other friends who have Turbosounds and they experienced the same issues so they sent them back for repair or replacement.