I am not sure what device that is, but i have had lots of hum problems over the years.
the first thing to do is to take the device to another house and plug it in there. hum problems are usually caused by the electrical system you plug the audio device into.
I once had a nasty hum from a gallien-kruger bass head that only happened in my apartment. When I took the head to the store, no hum!
Try this first before you decide the unit is defective.
Hope this helps.
Jon
Jon Broderick
Guitar Tricks Instructor
www.GuitarTricks.com - Home of Online Guitar Lessons