Running your dac form a computer? The Chords need to see 5volts over the USB cable to function. But those 5 volts coming from any computer are noisy. Use the Isolate to feed the Chord a clean 5v of battery power. Cable is made with Mundorf wire and is handmade in Australia. Buyer pays paypal and shipping. Retail $195. Selling for $115 No trades please.