KRK Rockit 5 generation 1 problem (Hard noise!)

[denprins]

Since yesterday I have a problem with one of my KRK speakers.
This video will show the same problem:

youtube[dot]com/watch?v=KptxZbE72G8

Can anyone help me??....

Thanks!

Greetz, Dennis

 

[CoolCat]

What partitioning tests have you done?

I would assume you tried to swap ac cables.
then I would open the speaker cab and unplug the tweeter and woofer and swap with other cabinet.

this will eliminate if its the speakers or electronics.

its probably the electronics, a pcb board....that hum sounds like a ground, and could be a simple cold solder joint.
the only hum Ive heard like that, turned out to be a capacitor leg needed a little solder.

good luck...hate to hear KRK is having failures, seems recently a few posts about KRK having problems.

 

[denprins]

Thanks for your response!

Yes I have try to swap ac cables, but still the same hard noise.

I have tested a lot: I replace 4 capacitors, check all the cables.
But still a loud noise.

The problem is when I put the speakers (LV see picture) on that DC (started by 22v to 7v) comes to the woofer..