Plantronics ( PLT), despite a 31% boost in revenue, swung to a first-quarter loss from a year ago. The Santa Cruz, Calif.-based wireless headset maker said Tuesday that it earned $12.3 million, or 25 cents a share, in the quarter, a decrease from $21.7 million, or 44 cents a share, a year ago. Excluding items, earnings were 28 cents a share in the most recent quarter, lower than expectations of analysts polled by Thomson First Call of 31 cents a share. First-quarter revenue rose to $195.1 million from $149 million a year-ago on the strength of Plantronics' acquisition of Altec Lansing products last year. Sales, however, still missed First Call expectations of $198.6 million. Second-quarter guidance also fell short of Street estimates and sent shares down 11% to $17.30 in recent after-hours trade. Flextronics said it expects to earn 16 cents to 21 cents a share in the second quarter on revenue of $190 million to $200 million. Adjusted earnings are expected to be 22 cents to 27 cents vs. consensus of 36 cents a share on revenue of $209.million. CEO Ken Kannappen said that weaker demand was "primarily the result of macroeconomic factors contributing to a slowdown in the markets we serve. In light of the current environment, we reduced the level of marketing expenditures otherwise planned for our first quarter." In a separate announcement Tuesday, Plantronics announced that its board of directors declared a quarterly dividend of 5 cents a share. The dividend is payable on Sept. 8, 2006 to shareholders of record at the close of business on Aug. 10, 2006. Shares closed the regular session up 4 cents to $19.54.