The company has faced mounting criticism from analysts and consumers over its handling of the issue, leading to speculation that it will announce a recall.
The news comes a fortnight after Apple announced it would issue a software update to appease angry customers who have experienced problems with their iPhone 4 handsets, and will also refunds to those who have been inconvenienced.
The company says the iPhone 4 has been the most successful product launch in its history, but it has been tarnished by reports of reception problems. Initially, the company told users not to grip the handset in certain ways but research has revealed a display error in the mobile’s programming.
It found the handsets were sometimes displaying 4 bars when they should be displaying as few as 2 bars and says to fix this, it is adopting AT&T’s recently recommended formula for calculating how many bars to display for a given signal strength. This will be issued through a free software update within a few weeks.
Reports of problems with the iPhone 4’s antennae started surfacing shortly after the phone went on sale on 24 June. At that time some users claimed the signal strength fell away and calls were dropped when they gripped the phone on the lower left side.
A number of videos were posted on the video-sharing site YouTube show the extent of the reception issue, adding to the brand damage. Reports suggest that Apple has been deleting comments on its own forums that criticise the handset.