* Sony tumbles 10 pct after slashing guidance * Panasonic jumps to 2-1/2 year high after lifting f'cast By Dominic Lau TOKYO, Nov 1 (Reuters) - Japanese stocks inched higher on Friday morning, helped by solid earnings from the likes of Panasonic and mobile operator SoftBank Corp, but the mood was somewhat dimmed by a plunge in Sony Corp shares on a profit-warning. Sony, the maker of the famed Walkman music player to the game console PlayStation, tumbled 10 percent after it slashed its full-year operating profit forecast by 26 percent as its struggling TV operations fell back into red. Rival Panasonic was cheered by investors, with the stock up 5.9 percent to a 2-1/2 year peak after it lifted its earnings forecast on strong sales of products like batteries to industry clients. Sharp Corp, like its domestic peers which have been struggling against the onslaught of foreign rivals such as Samsung Electronics and Apple Inc, posted its first quarterly net profit in two years, beating market expectations. The stock was up 5.2 percent. The benchmark Nikkei advanced 0.3 percent to 14,365.43, rebounding from a 1.2 percent decline in the previous session. The benchmark is up 2 percent so far this week after shedding 3.3 percent last week. Adding to the positive sentiment, China's manufacturing sector expanded at the fastest pace in 18 months in October, official data showed on Friday, providing fresh signs of a stabilisation in the world's second-largest economy. A senior trader at a foreign brokerage in Tokyo said company earnings after Thursday's market close were a bit mixed but added that buy orders still outpaced sell by two to one. "People who have been active are traditional real money accounts in large cap stocks ... We've seen retail investors slowing down a little bit and institutional investors stepping up a little bit," he said. The broader Topix index was flat at 1,194.76, with trading volume at 30 percent of its full daily average for the past 90 trading days. Index heavyweight SoftBank jumped 3.7 percent after it reported a record six-month profit, spurred by strong sales of handsets, subscriber growth and a share price that has more than doubled this year. SoftBank was the most-traded on the main board by turnover, followed by Sony, Sharp and Panasonic. Ink-jet printer and electronic parts maker Seiko Epson Corp was untraded with a glut of buy orders after it raised its annual operating profit guidance by 57 percent to 58 billion yen. The stock was notionally quoted at 1,996 yen, up 25 percent from its Thursday's close of 1,596 yen. Underscoring the mix bag of earnings, TDK Corp dropped 3.9 percent to a three-week low, with analysts expressing concerns about its outlook on hard disk drive business. Nevertheless, the quarterly earnings season so far has sprung few surprises. Of the 83 Nikkei companies that have so far reported quarterly earnings, 58 percent of them either beat or met analysts' expectations, according to Thomson Reuters StarMine, in line with the previous quarter. The Nikkei has risen nearly 40 percent this year on the back of the Japanese government's aggressive monetary and fiscal stimulus.