Register your Koss Headphones. Once you have completed registration, you may send your warranty items to Koss. Along with your Warranty product please include: $9.00 for the return shipping and handling per stereophone (money order, cashier's check, or personal check: payable to Koss Stereophones), a note describing the failure, as well as your contact information: name, return shipping address, phone number and email. Please keep your tracking information on file. We will ship out warranty replacements within 72 hours of the product being processed via standard US mail or via UPS. and we will repair or replace them in accordance with our Limited Warranty. Ship your Warranty product(s) to: Koss Corporation Attn: Warranty Return 4129 N. Port Washington Avenue Milwaukee, WI 53212 Please allow 10-14 days for shipment delivery. If you would like to check the status of your warranty, please call Koss Consumer Sales at 1-800-USA-KOSS. For more Koss Warranty information click here.