CSR, which specialises in audio products using Bluetooth wireless chips, posted a jump in underlying operating profit to $39.3 million (25.5 million pounds), up from $23.9m million for the same period a year ago.

"Revenue in mono audio in China arising from the enforcement of hands-free driving legislation was strong," said chief executive Joep van Beurden.

One of a number of technology companies clustered in the eastern English university city of Cambridge, the company posted a two percent fall in revenue to $262.5 million over the same three-month period.

Van Beurden said third-quarter revenue would be in the $240 million to $260 million range.

Analyst Lee Simpson at Jefferies, who has a "buy" rating on the stock, said guidance for third-quarter sales was marginally below consensus at the mid-point, but it was "not really a deal breaker" as the firm reiterated it was comfortable with consensus.

Shares in CSR, which has a market capitalisation of just under 1 billion pounds ($1.54 billion), slipped 3 percent to 582.5p by 0725 GMT.

CSR's underlying diluted earnings per share stood at $0.18, twice its value at the same point last year.

The firm plans to return a further $25 million to shareholders via a share buyback, increasing its total return to $75 million.

"We continue to be well positioned for growth in our Core business," said van Beurden.

(Reporting By Mark Anderson; editing by Keith Weir)

By Mark Anderson