Updated from 1:03 p.m. EDTSAN FRANCISCO -- Sigma Designs ( SIGM) shares were hammered Thursday after the chipmaker disclosed a problem in its orders that caused it to ship more products than called for by the market's actual demand. The overshipments, which Sigma Designs characterized as a "one-time adjustment" during its fourth-quarter earnings conference call, resulted in a sales forecast for the first quarter that came in well bellow Wall Street estimates. Milpitas, Calif.-based Sigma Designs said revenue in the current quarter will be roughly $60 million, vs. the average analyst estimate of $76 million, according to Thomson Financial. In midday trading Thursday, Sigma Designs' stock was down 16%, or $4.05 at a new 52-week low of $21.21. Several Wall Street analysts lowered their price targets for the company's stock following the news. Deutsche Bank and UBS, which each had price targets of $75 on Sigma Designs, slashed their price targets to $43 and $48, respectively, although each maintained their buy rating on the stock. Sigma Designs develops chips for Blu-ray DVD players as well as for Internet-Protocol-based television set-top boxes made by firms like Motorola ( MOT) and Cisco Systems ( CSCO). In the fourth quarter, which ended Feb. 2, Sigma Designs boosted its revenue 145% year over year to $76.4 million, primarily due to strong sales of IPTV set-top box chips. Net income was $35.3 million, or $1.19 a share, vs. $4.6 million, or 20 cents a share, at this time last year. Excluding certain items, including a one-time $10.8 million tax benefit, Sigma Designs said it earned 80 cents a share. By that measure, analysts were expecting 83 cents a share. According to Sigma Designs, the recent order snafu stemmed from a large telecommunications provider ordering more set-top boxes than it actually delivered to consumers. "As a result the order during our first quarter will be much smaller than normal and the order rate for the second quarter should then resume at the ongoing rate of deployment," said CEO Thin Tran during a post-earnings conference call. Tran said the company expects to generate $300 million to $350 million in revenue for the fiscal year, compared with the $340 million expected by analysts, and said its gross margin would remain within 2 percentage points of 50%. Know What You Own: Motorola operates in the telecom equipment sector, and some of the other stocks in its field include Nokia ( NOK), LM Ericsson Telephone ( ERIC) and Alcatel-Lucent ( ALU). These stocks were recently trading at ($32.56, +1.43%), ($20.25, +0.90%) and ($5.52, +0.91%) respectively. For more on the value of knowing what you own, isit TheStreet.com's Investing A-to-Z section.