New Delhi, Oct 4 : Apple is internally testing the next iOS 17 update to fix overheating issues in iPhone 15 Pro phones which is likely to be available either later this week or next week. The iOS 17.0.3 will not reduce the performance of the A17 Pro chip, according to MacRumors. The same bug fix should eventually be included in iOS 17.1, which is currently in beta and is expected to be released in late October. Not all iPhone 15 Pro or Pro Max users have experienced overheating, and it's unclear how many users have been impacted by the issue. Apple has identified a few conditions which can cause new iPhones to run warmer than expected, including a bug in the iOS 17 software update and some third-party apps like Instagram. The device may feel warmer during the first few days after setting up or restoring the device because of increased background activity, the company said in a statement earlier this month. 'We have also found a bug in iOS 17 that is impacting some users and will be addressed in a software update,' the iPhone maker said. The new titanium material on iPhone 15 Pro, paired with its aluminum substructure and new system design, result in better heat dissipation than any prior stainless steel Pro models. iPhone 15 Pro and iPhone 15 Pro Max do not suffer from overheating due to their design, contrary to some reports. Third-party apps that Apple is currently aware of that overload the CPU and cause the iPhone to run warmer than normal include Asphalt 9, Instagram and Uber. Instagram already issued a fix on September 27 (v302) to address its issue. /IANS