Customers can get hold of the illegal cards from websites and on the black market. They then pay the lowest monthly subscription to the services, which also gives them the set-top box required to receive the signal. The illegal smartcards are used with box to receive the subscription channels for free.
Stuart Prebble, chief executive of ITV, said, "We have a piracy issue. We know exactly why we have a piracy problem and we have an investigation going on."
It is believed that ITV Digital's piracy problems could be a result of the version of security software it uses. The broadcaster is said to use a version of Vivendi-owned Canal+'s MediaGuard conditional access software, which is not the most up-to-date.
The piracy issue was raised last week at the Royal Television Society Convention by Telewest chief executive Adam Singer. He is understood to have decided to publicise the problem after becoming frustrated that Telewest's own subscription channels are suffering at the hands of the pirates.
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