2005 ES330, 247K Mileage.

I bought this car from the 2nd owner, it has an aftermarket stereo installed which I never use.
Recently, it's been making these weird constant electric noise and I hear it coming out of the speakers. I've attached a video for reference.
It also whines and fluctuates with the engine RPM.

I did some googling and it could possibly be an ground issue. I'm not sure how I would go about fixing that but I was wondering:
Can I just disconnect the powerline from the stereo altogether? I don't ever use it nor do I forsee any reason to use it. Would that be an easier solution?

 

Here's what the stereo system looks like.

 

Try a noise filter like this.

Might not work since that head unit is not exactly the highest quality.

 

Try unplugging the headunit to see if goes away. Any upfiting of anything else recently like led headlights?

 

Hello,

If you actually never use this Head Unit and think that your life will benefit without it, you can simply pull a 10A RAD No.2 Fuse out to Disable it completely, provided it was wired by anyone other than a spider monkey or its relative, which, unfortunately, happens a lot more often that it seems.. Here is a Fuse Diagram for your car.

With that, if you actually want to fix the issue while keeping a functioning Head Unit, first I would suggest to check the Factory Capacitor under the Hood, here is a Parts Catalogue that shows its location. If that's good, you will likely need to pull the Head Unit out to assess the quality (if any) of the installation, and to look for any potential issues with the way the Factory Wiring was spliced in. There really isn't anything too complicated about it, might as well at least try it before waving the Head Unit goodbye..

Hope this helps and best of luck!