The following lines were added (+) and removed (-):
=== Noise On The USB Interface ===In one DJ setup a [[USB External Audio Adapter]] was substituted for the laptop onboard sound I an attempt to stop the ground loop noise issue. The test failed. Even though the USB sound card delivered higher quality sound, the interference ground loop noise was carried on the USB cable into the [[USB External Audio Adapter]] and from there into the mixer and amplifier.It is possible a ground loop isolator on the USB cable would be a better solution, as it would stop the noise without having any impact on audio quality since the signal at this point is still data. Isolation improves common-mode voltage, enhances noise rejection, and permits two circuits to operate at different voltage levels. It also tends to save test equipment, as well as PC itself. It is much more difficult to find a USB isolator than a basic audio or electrical isolator. One is known to exist and the [http://www.circuitsathome.com/mcu/usb/usb-isolator USB Isolator] is discussed on an article and [http://www.hvwtech.com/products_view.asp?ProductID=1226&utm_source=Google&utm_medium=Product+Search&utm_campaign=Product+Search+%28Aug10%29 sold by HVW Technologies]. DigiKey, a well known source for [[Purchasing Electronic Components]] also offers [http://parts.digikey.com/1/parts-kws/usb-isolator-board USB Isolators]. === RCA / Line Input Audio ===* [http://www.newegg.com/Product/Product.aspx?Item=N82E16882586207&cm_re=Ground_Loop_Isolator-_-82-586-207-_-Product Ground Loop Isolator] at Newegg.com for $14.99 === USB ===* [http://www.hvwtech.com/products_view.asp?ProductID=1226&utm_source=Google&utm_medium=Product+Search&utm_campaign=Product+Search+%28Aug10%29 USB Isolator Board]