Red97LT1

Guys i am getting a popping noise when i turn up the volume or turn it down.I just installed this alpine 7893 yesterday and it sounds good except for the popping noise.I even get it when i hit the buttons,but it only does it when i have bass.If i am listening to a news broadcast then it's fine. I know it's not the ground,i have used 6 different locations and it is still there.Any ideas?

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