I have a custom box I made with a 12 inch L5 and a 800 watt sony amp the head unit is also a sony. I have a high pitch whine that comes from the unit during startup and last for about 15 minutes before it slowly goes away or you cant hear it much anymore. I noticed when I give my truck gas or acceleration sometimes it makes it worse but not all the time. Any suggestions??

 

You may want to check your grounding. Where is you amp located and where is it grounded? Also where ever you have grounded, is it to bare metal?

 

Hello, amp is in the back passenger side, and it is grounded to a two bolts in the frame not sure of they are bare metal. Thanks

 

Engine whine is really common, make sure that you buy good quality RCA cables, not ****ty radio shack stuff. Another thing that causes the whine is when you run your RCAs next to your power wire for your amps. Run the power wire on the other side of your truck and it should eliminate your problem.

 

Thanks for your help guys I will try this and let you know!

 

Where do you live at? My truck did that in cold weather with the factory stereo and even does it with the upgraded stereo. It only does it when the temps are 0 or colder and changes pitch with engine RPM and goes away after warmed up. I never have figured it out yet.

Tim

 

Sounds most likely to be a ground issue. If you're grounded where I think you are (the stock bolts to hold the jack down) make sure all the paint is cleared away from the ground eyelet. Should eliminate the problem

 

Hello guys, I live in northern Kentucky but it has been making this noise regardless of outside temperature but the sound seems to go away 30-60 minutes after driving wither that or my ears get used to the sound. I sanded my grounds and checked them and still have the noise! I believe I am now lost also on the RCA cables I do have high quality cables I do believe! Thanks for your help guys any more suggestions welcome!

 

are your amp power cables and rca cable next to each other at any point?