Complaints from UK householders about silent calls from call centres have more than tripled, says Ofcom.
Typically, these occur when call centres with automated systems dial more numbers than staff can deal with.
Complaints from consumers, left frustrated as they had no idea who the call was from, hit 1050 in September from 300 complaints 12 months earlier.
Regulator Ofcom is publishing advice to consumers about how to complain about silent or abandoned calls.
It has taken action against various companies following repeated cases of silent calls.
In September, it handed down the maximum possible fine of £50,000 to Barclaycard for what it described as the "most serious and persistent" case of silent calls ever seen by the regulator.
Advice
Information is also being published for consumers about how to complain about problems with telephone service providers, such as mis-selling.
This includes the process called "slamming", when a customer has their service provider changed without their knowledge.
This was increasingly a problem in the fixed-line market, Ofcom said in a report.
"Action against the scourges of slamming and silent calls remain priorities for Ofcom over the coming year," said chief executive Ed Richards.
The report added that complaints about mobile phone cashback deals - when customers bought a handset up front and then were refunded the cash over the course of the contract - had dropped from 600 a month in September 2007 to 70 a month in June 2008.
In the worst cases, restrictive terms and conditions - which were often difficult to understand - meant some failed to receive their promised cash. Other retailers went bust, leaving customers without their money.
Source: BBC News, 24th November, 2008
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