Days after the latest lineup of Apple products hit stores worldwide, some of the first owners of the iPhone 15 Pro and Pro Max are complaining that the phones are overheating.

The iPhone 15 Pro Max, rolled out earlier this month, is the priciest phone in the latest generation at $1,200, nearly 10% more than last year’s top-of-the-line iPhone. The iPhone 15 Pro is one step down, selling for $1,000.

While not all owners appear to be affected, a number of posts surfaced in the iPhone subreddit in recent days complaining of painfully hot devices.

“Just had this issue now weirdly enough,” wrote one person. “Haven’t had any problems charging the 15 Pro before. All of a sudden it became one with the sun. Weirdest part was the WHOLE phone was hot. No localized heat spots.”

Another iPhone 15 Pro owner claimed to have returned the device saying that, after charging at night, the phone became “downright dangerous” by the morning.

“Listening to Spotify while using iMessage and it’s uncomfortably hot in my hands caseless. Even with a case it’s quite warm,” another person wrote. “This is pretty alarming as I’ve owned every iPhone since the 6 and never experienced this type of issue.”

Apple’s technical support advises iPhone and iPad owners that the devices might feel warmer when they are set up for the first time, restored from a backup, or wirelessly charged, among other situations. Apple advises that a device that feels warm in those situations “will return to a regular temperature when the process is complete or when you finish your activity.”

While Apple’s website advises that, “If your device doesn’t display a temperature warning, you can keep using your device.”

As of yet, it’s not clear what’s behind the overheating reports, but if users are still dealing with painfully hot phones well after the initial setup phase, it could mean a greater issue with Apple’s flagship phones.

TF International Securities analyst and Apple expert Ming-Chi Kuo told ZDNet that he believes the problem is “likely the compromises made in the thermal system design to achieve a lighter weight. A “reduced heat dissipation area” and “the use of a titanium frame” combined to “negatively [impact] thermal efficiency,” he told the tech publication.

Kuo believes that Apple can roll out a patch through a software update – but at a cost.

“[The] improvements may be limited unless Apple lowers processor performance,” he said.

Nexstar reached out to Apple about the reports but did not immediately receive any official comment.