Investors have their reservations about Nokia's ( NOK) efforts to peddle cheap phones in poorer countries. Nokia posted third-quarter earnings Thursday that were in line with expectations, but Wall Street wasn't pleased by its reliance on low-price, low-margin phones. Shares of the Finnish cell phone giant fell 6% Thursday after the company said it sees margins narrowing further in the fourth quarter as its average phone price continues to fall. The problem is that tech investors like their growth stories straight up, unadulterated by things like profit-margin problems. A digression from that plot can anger fans. Nokia is the No. 1 player in an industry on track for yet another year of record growth. Typically, about half of that growth comes from selling fancy phones in affluent countries. But now the curtain is going up on new markets like India, Africa and Latin America, where incomes are smaller and cell phones have to be significantly cheaper. "More units, worse price, lower margins -- that's the worry," says one New York hedge fund manager. Nokia sits in a tricky spot with limited options. Feeling the heat from handset rival Motorola ( MOT), Nokia has to remain strong in every segment of the market or risk losing a hard-won share of the business. And with Motorola batting a thousand with its popular Razr phone, Nokia's game is starting to look a little faded. "Unit volume was the one thing a bit disappointing to me," says Sanford Bernstein analyst Paul Sagawa, who has a buy rating on Nokia and a neutral on Motorola. "The 9.5% sequential growth puts it behind Motorola, Sony Ericsson and LG. I think they likely lost a small bit of share in the quarter, all of that coming in North and South America.