Over the past two weeks my car an 08 fg xr6t sedan with premium sound it has started making a really loud cracking noise through the speakers it seems as if something is shorting out or my icc could be stuffed. It happens when: Car is running or even when just on accessory with engine off.When listening to anything: radio,cd,aux.or even when the audio is fully turned off.Day night raining whenever it just happens.I have checked, All my earths, battery, fuses, speakers even pulled my icc out to make sure everything is plugged in correctly and not loose but still have found nothing unusual. Its really starting to annoy me so if anyone has had a similar experience or ideas to what it may be would be greatly appreciated.