Top U.S. consumer electronics chain Best Buy Co reported a lower-than-expected quarterly profit on Tuesday as weakness in the entertainment software and appliance categories offset market share gains.

The retailer, which has steadily gained market share after main rival Circuit City closed its doors, said net profit fell to $158 million, or 37 cents a share, in the second quarter that ended on August 29, from $202 million, or 48 cents a share, a year earlier.

Excluding a tax impact, the profit was 40 cents a share, a penny below analysts' average forecast of 41 cents a share.

Best Buy, whose total revenue rose 12 percent to $11.0 billion in the quarter, raised its outlook for the fiscal year.

The retailer's stock was down 3.8 percent at $38.86 in trading before the opening bell.

(Reporting by Dhanya Skariachan in Bangalore, editing by Dave Zimmerman)