Not sure where to post this... I'm trying to play music from my iPhone through my new Behringer PA system. I found a miniplug adapter that splits the signal through two quarter inch plugs. I plug each one into its own channel, then send the signal hard right and hard left in each channel to create stereo. It works except it sounds out of phase, or slightly tremelo, if that makes sense. The signal comes in and out and doesn't sound crystal clear. What am I doing wrong?