Mbox mini hum!

[Chrisnic]

I recently purchased the Behringer Truth B1030A monitors for my Pro Tools LE 7.4 system connected with my Mbox mini 2. I have noticed that there is a high pitched humming noise when Pro Tools is opened, or even when im playing music on iTunes through my monitors.
I have balanced cables connecting my monitors to my mbox monitor outs.

I cant really think what else the problem could be, not unless its the USB cable?

Thanks

[getz76]

First thing I would test would be to plug the monitors into a different electrical outlet. If that changes the noise, you have narrowed down your problem.

Else, change out all cables if you have extras available.

[DigiTechSupt]

There's also a section in the General Troubleshooting thread that addresses some causes and solutions for noise with Mbox devices.

[Chrisnic]

Would it matter the cost of the balanced cables? They were about £6 each. Would it be better to get more expensive ones?
Also, there is NO hum/buzzing noise coming out when i plug my headphones in, only buzzing when my monitors are plugged in.

[Philthy]

I put direct boxes with ground lifts enabled between each channel of the outputs and my destination... it fixed the problem for me. I'm using unbalanced cables from the MBox to the direct box and then balanced XLR's to my destination.

[Chrisnic]

i purchased the Behringer HD400 hum destroyer and it eliminated the problem completely! great product, would advise anyone to get this if having a similar problem.