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LONDON, Oct 27 - Britain's Virgin Media added 6,300 net new cable customers in the third quarter, reassuring investors after a disappointing second quarter, as subscribers showed a willingness to pay for higher quality services.

Much like its fierce rival BSkyB, the cable operator has focused on cross-selling products to existing customers in recent quarters and attracting perhaps fewer but more valuable users than growing its base for the sake of it.

The results should go some way to reassuring investors, after the shares fell in July on a disappointing second quarter when it surprisingly lost 36,000 cable customers.

The solid performance in the third quarter and the focus on higher value customers meant the average revenue per user was up 3.2 percent to a record of 47.86 pounds, helping to take group revenue in the three months up 2.2 percent to 1 billion pounds, in line with forecasts.

Operating cash flow was up 2.8 percent to 398 million pounds, broadly in line with forecasts of 403 million pounds according to a Reuters poll.

The group also announced an extension of its share buyback program of up to 250 million pounds, in addition to the 625 million pounds it announced in July.

(Reporting by Kate Holton)