Hi everyone, I am not sure if where I have posted this is right but here goes.

I have a Z506 Logitech 5.1 surround sound. I purchased about 2 months ago brand new and didn't have a problem at all until about 3 weeks ago.

The issue has been on and off. After everything I have done to resolve this issue I have narrowed it down to the subwoofer and possibly the on/off control/speaker.

I have uploaded a small but hopefully long enough clip for you to get the jist of the sound. This sound is the same no matter the volume on the control speaker with the exception of being completely set at 0% volume, the loudness of this sound is amazingly high therefore I could only go for a couple seconds audio I have unplugged the 4 other speakers (back left, right and front left +centre) the only one left connected to the subwoofer is the on/off speaker that controls the volume.

This sound persists no matter what. I have tried switching different mains power outlets, extension all sorts.

I only use this system for my PC but even disconnected from it, it must be something with the woofer. Link below for small youtube audio clip

https://www.youtube.com/watch?v=QVAjbAAXrdw

It's a very short audio capture but that noise is constant and very very loud. I have been banging my head off the table for a while now so it would be great if anyone who has knowledge of this can enlighten me a bit

Thanks in advance.