Viacom tumbles as Wall Street falters

(Close): US stocks finished slightly lower on Tuesday, after a choppy day set off by sharp declines in Japan.

The Dow Jones was down 12.67 points at 16,014.38, while the S&P 500 shed 1.23 at 1,852.21 and the Nasdaq fell 14.99 to 4,268.76.

The US markets wavered betweens gains and losses throughout the day.

One of the biggest fallers was media giant Viacom, which saw its shares fall 17.76% after it reported a bigger-than-expected drop in quarterly revenues.

A 5.4% fall on the Japanese Nikkei shook some investors, as did a fall in US crude oil prices.

"We still believe this volatility is going to continue until commodity prices settle down, and that hasn't happened yet," said Alan Skrainka, chief investment officer at Cornerstone Wealth Management.

Brent crude fell 6.4% to $30.78 a barrel, while US light crude dropped 4.7% to $28.30 a barrel.

Shares of oil company Chevron fell 3.6%, and Exxon Mobil declined by 1.3%.

On the Dow, retailer Home Depot was the top gainer, adding 2%.