I have this new Trent IMP70D 7000 mAh battery pack bought some time back. It works fine as such but the problem is that it charges my iPhone only with its supplied cable. When I try using my stock iPhone Cable it refuses to charge the phone. I also tried those cheap eBay cable and that too does not work. These cables work fine when used with stock iPhone charger and phone is charged through wall socket. I know this is not phone issue because it behaves the same with my iPhone 4, 4s and 3GS. What might the issue ? I don't get any message or anything on the phone. It just does not charge.