I bought AKG 550 headphones from Sonic Electonix. Unfortunately, they soon developed an issue rendering them (the phones) unusable. They suggested to follow up with the manufacturer, which I did. However, the AKG was not helpful at all, they bounced me from "Pro" department to "Home" and I ended up asking Sonic Electronix for help. I ended up paying only one way shipping and got a replacement device even though it was beyond 60-days replacement window. Needless to say, I am very appreciative with the service and communications I receive from the Sonic. Thank you!