How do I properly setup the Fretlight System with my computer and amp? I hear humming or noise out of the amp with the LEDs on.

From Fretlight Knowledgebase

The Fretlight Learning System utilizes 132 LED's which naturally produce slight electronic noise that, if improperly connected with your computer and amp, could be heard through your guitar amp. Any proper musical setup should ensure proper grounding. The following list of DO's, DON'Ts and Cautions will help you ensure a good grounded signal and clean sound with your Fretlight Guitar.

DO:

• When your computer is connected to a power outlet, make sure it has a grounded three-prong plug. Most computers come standard with grounded power supplies and cables.

• If you have a laptop, you can certainly use it without connecting it to a power supply, thereby running it of its internal battery.

• Make sure that the Fretlight-to-USB cable is plugged into a root USB hub on your computer. That is likely one of the USB ports on the back of a desktop computer.

• Make sure that you are plugging into a wall outlet that is grounded— in other words, has three prongs as shown at left.

• While connected to the computer and amp, at the same time, make sure that you use the pickup that is closest to your guitar's bridge.

DON’T:

• Do not use a two-prong plug or a 3-to-2 adapter plug. • Do not use a two-pronged wall outlet—only use a three-pronged, grounded wall outlet.

• Do not use an external USB hub. The Fretlight must be connected directly to the root hub of your computer.

CAUTION:

• Try not to use power strips or extension cords as they WILL introduce extra noise into the system. For best results, connect your system as shown at left.

• Make sure that you’re using a shielded guitar cable. There is a difference when it comes to extraneous noise introduced into the system. We recommend using a name brand cable.