In a research note from KGI, a financial analytics group out of China, oft-cited analyst Ming-Chi Kuo places the responsibility for the shortages in new iPhone 5 connectors squarely on the shoulders of a shift in the specific supplier of the connector from Foxconn (Hon Hai) to Foxlink (Cheng Uei), due to lower yield rates of the new unit type from Foxconn.
AppleInsider also reports sources saying that Apple has requested Foxlink pick up the slack and dedicate more workers and production lines to the Lightning cable production line.