Apple is gearing up to launch its next-gen iPhone 7 and 7 Plus in a couple of weeks. Meanwhile, owners of the two-year-old iPhone 6 and 6 Plus have been complaining about a flickering gray bar at the top of the screen and the unresponsive touch screen. Many users have reported the issue on Apple’s support forum. Some iPhone 6 owners thought it was caused by a recent iOS update. But the actual cause is something else.

Apple iPhone 6S

iPhone 6: The issue is caused by a strain on touchscreen chips

According to the gadget teardown and repair site iFixit, if your iPhone 6 or 6 Plus isn’t registering your fingers’ touch, it’s because of a strain on the smartphone’s internal touch-screen chips. It’s a big problem because the touchscreen is the main way to interact with the device. You can’t even call or text someone without the ability to tap the screen. Citing Jessa Jones of iPad Rehab, iFixit says the normal daily use of the iPhone 6 Plus could create a “small crack or separation in one of the balls that underlie either of the touch IC chips on the board.”

After some use, you might notice the gray flickering bar and the screen may become unresponsive. But it comes back quickly after a hard reset. However, the unresponsiveness of the screen becomes far more frequent as the crack widens, causing a separation of the chip/board bond. If your iPhone gets accidentally flexed or bent, it could entirely damage the relevant parts.

What are your options?

Jones said the issue is caused by changes in the way the iPhone 6 Plus was built compared to previous generations. The iPad Rehab showed how the relevant components in the iPhone 5S were protected with a tough metal shield, but the same parts in the iPhone 6 Plus are protected by a thin film that is no match for metal shielding.

Apple seems to have recognized the issue in the support forum. The company has recommended affected users to check out a support page about unresponsive touchscreens. However, there is not much you can do, as Apple has not initiated a replacement or repair program for this issue. Assuming your iPhone is still under warranty, you may seek a free replacement. If your device is out of warranty, you may have to take it to third-party repair shops to get the touch-screen chips replaced.