Hercules DJ Console MK2 Hiss Fixed Sort of this is a workaround I found after trying every solution others have tried
When you connect the DJ Console to your amplifier you might here a big loud hiss noise even with the faders turned down on the console
I tried to use ground loop isolators, separate usb powered hubs different laptops, different cables bla bla. Nothing cured the loud hiss I tried all different Virtual DJ settings different Asio, WDM Still the loud Hiss. So after hours of trying I got my old Stanton 2 Channel DJ Mixer from the loft Plugged in the MK2 into the line in then out of the Stanton to the Amp guess what no more Louds Hiss.
This solves my problem for now I hope it helps you