Radio sound comming from my speaker

So today I turned on my pc and powered on the Sub woofer speaker.
Then I heard music and voices coming from the speaker.
I could clearly hear it was picking up a radio station   

When I first installed my Pc more than 2 years ago I heard something like that
For all this time If I held my ear against the speaker I could hear a radio noise
But it was so mild I did not really pay attention to it because it didn't bother me.   

and so today the volume was really increased   
If I sit In my chair I can just listen to the sound that is coming out of it.
I read on some forums it could be the cables picking of some Radio waves.     

In this condition you can't really listen to music because you can hear the radio sounds really easy
When I turn the volume up or down the music doesn't change.
and When I unplug the speaker from the pc the volume goes down really low what is was before only a bit louder than that.

Anyone had this problem before?   
And has a solution for this?

When the pc is turned off you can still hear it so it isn't coming from windows   

so any thoughts?  

Humm! Ghost in the machine!?   

I had a similar case at work once, we could pick up a local AM radio station on a piece of cable connected to a mixing table, very weird but not completely unheard of.

It probably is a ground loop that is picking it up   

and need some Ferrite Beads to get rid of it (hopefully)

Only problem is where do I buy one