The semiconductor industry's inventory problems continued to plague Xilinx ( XLNX) in the third quarter. For the second time in a month, the chipmaker lowered revenue guidance, saying it now expects a sequential decline of 11% to 12%, up from its previous forecast for a decline of 5% to 8%. The old forecast came in a Dec. 8 midquarter update in which the company updated its first estimate for 2% to 6%. The latest reduction reflects "weaker than expected turns business in the month of December impacting all geography." The term refers to sales that are booked and shipped in one reporting period and measures a company's ability to keep inventory moving out the door. The new revenue estimate comes out to roughly $355 million to $359 million. Analysts surveyed by Thomson First Call were expecting Xilinx to earn 20 cents a share on revenue of $378.4 million in the December quarter. The shares were recently down $1.34, or 4.7%, to $27.10 on Instinet.