The Radio City Rockettes (search) might be high-kicking this holiday season to Christmas (search) tunes controlled by a computer.

With musicians planning to strike, the possibility of canned music looms over Radio City Music Hall's (search) famed "Christmas Spectacular (search)," set to open Nov. 3 for 10 weeks.

Although the show could still go on with replacement musicians or electronically synthesized music, other unionized Radio City employees could refuse to cross the picket line, threatening to shut down a show that has entertained children and adults for seven decades.

The labor cliffhanger is not likely to end until opening day, when spectators from around the world hope to start lining up for a show that carries ticket prices of up to $250.

The orchestra's five-year contract expired in May, and meetings since then have failed to produce an agreement with Local 802 of the American Federation of Musicians on salary and overtime issues.

On Wednesday, hundreds of musicians and supporters staged a boisterous, music-filled protest on Sixth Avenue behind police barricades, in front of the hall.

"Don't let Cablevision $teal Christmas," read the words on red and green T-shirts worn by the protesters. Cablevision owns Madison Square Garden, the Knicks, the Rangers and the Radio City Entertainment company that owns the show. An inflated cougar with bared teeth faced the protesters — a counter-reference to the blown-up rat that often accompanies New York union protests.

Radio City Entertainment released a statement saying it "has offered our musicians an extremely fair contract proposal. ... The contract includes increases in salary and benefits and fully protects the existing overtime system. They have rejected that proposal and walked away from the table."

Should a strike occur, Radio City is "reaching out to orchestra musicians all over the world," according to company spokeswoman Michael Cordova. The company reportedly approached out-of-work New Orleans musicians who were recently in New York playing a Hurricane Katrina fund-raiser. But they declined because of the labor dispute.

"This is about union-busting by a corporate giant digging into the pockets of the musicians," said trombonist Mark Johansen, one of the union's negotiators. "At every negotiating session, we've been met with threats, 'If you don't accept this or that, we'll hire other musicians or use tape. Take it or leave it.'"

He said Radio City Entertainment is trying to cut the musicians' base pay of $133 per show, which is about $40 less than what standard Broadway musicians are paid, Johansen said. At the height of the Christmas season, the orchestra works as many as six 90-minute shows every day — at overtime pay beyond the first two. The musicians must play at least 12 shows a week.

On average, Johansen said, a musician doing 150 of about 200 shows in the run would make about $25,000; orchestra members also receive very basic year-round health benefits.

"They work like dogs — once a year like the people who sell Christmas trees. For many, this is their main job, their livelihood," said Cenovia Cummins, a violinist who fills in for musicians during the 10 weeks.

Union members said the company had agreed to keep the contract's overtime clause, but salaries would be cut. The musicians said Radio City Entertainment offered an increase of 1.5 percent while they asked for about a 3 percent cost-of-living raise. But the company said a second orchestra would be hired, which would mean the musicians' income would be cut in half, they said.

Radio City Entertainment would not give details of their offer, and said they do not comment on negotiations.

The president of Radio City Entertainment, Jay Marciano, called the union "greedy." He said, "There are new synthesizers that can re-create orchestras," producing "canned music" for anything from "Silent Night" to the high-kick tunes.

There are no talks scheduled, and the union authorized a strike on Sept. 28.

A four-day walkout by Local 802 shut down nearly all Broadway musicals in March 2003. But when the union struck the New York City Ballet in 2000, 13 performances of "The Nutcracker" went on as scheduled with taped music.

The unionized Rockettes reached their contract agreement last week.