Speakers crackle when the engine is running

[BirdBirb]

I have some cheap but functional aftermarket speakers from Walmart and a cheap touch screen head unit found online so i'm honestly not sure the brands. But i have a 2001 ford explorer sport trac and ever since i put the radio in i have had the issue where the speakers crackle with the music or bass but only when the engine is running. If i turn the truck on to accsessory with the engine off i can crank the speakers up loud and they sound perfect. If anyone has any slight info about this i would appreciate it

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[1aespinoza 10+ year member]

If anyone has any slight info about this i would appreciate it

Try grounding the radio chassis to bare metal. Since it is the radio straight to the speakers, if the issue remains, I would just assume the radio is faulty. Was the old radio making any noise?

 

[Thor230]

Your alternator makes AC power then is rectified then the DC is sent to your battery which acts as a filter however their is still a small ripple of ac in that DC power going into your amps and this is why you hear that sound with the car on . In home audio the ac is rectified then sent through a cascade of capacitors because different size capacitors filter different frequencies better then others so ideally they use several sizes and this cleans up the power so that the amp has better SQ, but in car audio we seem to have forgotten the importance of capacitors because we were told that they don't put out as much power as a battery therefore they are junk and this is unfortunately a concept born out of ignorance,

Long story short add a stiffing cap and that should do the trick or add one after the battery under the hoon then add a cap before each individual amp (if you have several amplifiers and batteries)

 

[audiobaun 5,000+ posts]

I would run another ground wire to cleaned off metal. Sometimes there is a Metal Bracket under the dash that generally work well. You can try several locations to see with a long 12-14ga wire to see if it is in fact a bad ground or possible an Internal issue with the HU that may still,be under warranty to replace. Thats where Id start