It will pour £10-15 million into improving the service broadband customers receive after some complained of long waits to have calls answered and months of delays before their broadband was installed.

The TalkTalk service, offering “free” high-speed internet access to all customers paying £20 a month for their landline phone, attracted an unanticipated level of customer interest when it launched in April 2006.

Chief executive Charles Dunstone acknowledged that it was vital to “work to further build the service levels at TalkTalk following the problems we incurred at launch”.

By spending the extra money, Carphone Warehouse aims to “protect the brand and proposition for the longer term”, it said.

But share prices fell after shareholders voiced concerns that the extra spending on disgruntled customers will weaken the phone company’s revenues.

Find out more about TalkTalk broadband

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