Napster Inc. narrowed its loss Thursday thanks to a bump in subscribers and Web traffic, but shares slumped despite beating Wall Street estimates.

Napster reported a third quarter net loss of $9 million (-21 cents per share), a 33 percent improvement on a loss of $13.6 million (-32 cents) from the same period a year earlier. Twelve analysts surveyed by Dow Jones & Co. Inc. had projected a loss of 28 cents a share.

Revenue for the Los Angeles-based Internet music provider was up 9 percent to $25.5 million mainly due to a 20 percent increase in premium subscribers and a 42 percent bump in unique monthly visitors to the company’s ad-supported Web site.

In September, Napster announced that it had hired UBS Investment Bank to advise it regarding a possible partnership or sale. Napster’s Chairman and Chief Executive Chris Gorog declined to comment on the matter during the earnings announcement.

Shares in Napster were down 9 cents to $4.36 in early trading Thursday.