Apple chief executive Steve Jobs was made aware of possible problems with the antenna on the new iPhone 4 before its launch, according to reports.
The company's senior antenna expert, Ruben Caballero, told Jobs during design testing for the device that there could be issues with the antenna that might cause calls to be dropped, said a Bloomberg report citing "a person familiar with the matter".
The report also claimed that a carrier partner had raised concerns about the antenna before the release, according to another person "familiar with the situation".
V3.co.uk contacted Apple for comment on the reports, but had not received a reply at the time of publication.
The iPhone 4 has been plagued by complaints of calls cutting out if the device is held in a certain way, leading to US products ratings group Consumer Reports saying that it could not recommend the device.
Apple responded by claiming that all mobile phones suffer from this problem if held in a certain way.
"Gripping any mobile phone will result in some attenuation of its antenna performance, with certain places being worse than others depending on the placement of the antennas. This is a fact of life for every wireless phone," Apple said.
The company has also claimed that the problem is the result of miscalculated signal strengths that cause the phone to show more reception bars than it should.
Apple has called a press conference for 16 July at which it is expected to address the issues facing the iPhone 4 in more detail.
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