You can't just buy an interface cable, that's their copy right protection, that's why I take very go care of my interface ( they can't be replaced). They will replace a broken or damaged cable or one that doesn't work, but you have to send your old one into them. If you have your receipt from when you bought it they might help you out, but I doubt it. I think the only way your going to get a new cable is to buy a new sim. Go on their web site, they have a big write up about all of this.