The iPhone 6 and iPhone 6 Plus have been out for more than a month now, and while the launch went well for the Cupertino-based company, it would seem some owners are experiencing less-than-stellar issues with their handsets.

Within the Apple Support community, many owners of 128GB variants of both the iPhone 6 Plus and iPhone 6 are reporting issues with repeated crashes of their handsets. Some owners are even experiencing boot loops after their device crashes and tries to restart. According to a report published by MacRumors, the issue seems to be plaguing owners of the aforementioned variants that also have a large app library on their handset.

It is believed that it could be a hardware issue with the 128GB models, but the exact cause of the issue is still unknown at this point.

However, BusinessKorea is reporting that “industry contacts” speaking to the publication suggest the problem could lie with the triple-level cell (TLC) NAND flash included in these particular models. Previous, Apple utilized a multi-level cell (MLC) NAND flash:

“Some in the industry point out that considering that technical defects mainly occur in the 128GB version of the iPhone 6 Plus, there might be a problem in the controller IC of triple-level cell (TLC) NAND flash. […]

As numerous reports of low read performance of the Samsung SSD 840 and 840 EVO using TLC NAND flash have surfaced on the Internet, a problem in the controller IC is considered to be the more likely cause of the defects.“

As noted, the only way to fix the issue is to bring the plagued iPhone 6 or iPhone 6 Plus back to Apple and have it replaced.

Have you experienced any of these issues with your own 128GB iPhone 6 or iPhone 6 Plus?