PortalPlayer ( PLAY) had more bad news for investors on Monday. The iPod chipmaker announced first-quarter earnings that fell far below analysts' estimates. Worse yet, instead of an expected healthy profit, the company forecast a potential loss in the second quarter on sales that were up to 50% below the Street's estimates. The disappointing earnings report came less than two weeks after PortalPlayer announced that Apple ( AAPL) had chosen a different supplier for some of its upcoming iPods. That announcement apparently weighed heavily in the company's outlook. "After completing a strong first quarter, we are very disappointed with the product transition setback that we announced," company CEO Gary Johnson said in a statement. Investors sold off the stock on the news. In recent after-hours trading, PortalPlayer shares were off 41 cents, or 3.6%, to $11.10. In the first quarter, PortalPlayer earned $6.5 million, or 26 cents a share, on $72.3 million in sales. In the year-ago period, the company earned $7.8 million, or 31 cents a share, on sales of $44.5 million. Not only did earnings drop from last year, but also they fell below analysts' forecasts and the company's own guidance. Those polled by Thomson First Call were expecting PortalPlayer to earn 35 cents a share on $73.9 million in sales in the just-completed quarter. In January, the company had predicted earnings of 28 cents to 38 cents a share on sales ranging from $70 million to $80 million. Looking forward, PortalPlayer predicted that its bottom line in the second quarter would range from a loss of 3 cents a share to a profit of 5 cents a share. The company forecast that its sales would range from $30 million to $40 million. Wall Street had previously predicted that the company would earn 27 cents a share in the current quarter on $61.2 million in sales. In the same quarter a year ago, PortalPlayer earned $6.3 million, or 25 cents a share, on sales of $44.6 million Shares of PortalPlayer closed regular trading up 46 cents, or 4%, to $11.51.