I recently had the frustrating experience of trying to figure out why Bluetooth devices wouldn’t connect properly to my iPhone 16 Pro Max. I bought the phone on launch day, and it seemed fine at first. However, in December 2024, I started noticing instability.

The annoying issue was that any Bluetooth device paired to the phone would randomly fail to reconnect after a certain period. The timing was unpredictable. AirPods would connect but then fail to work, CarPlay would rarely function unless I completely re-paired the device (and even then, it was hit or miss), and I noticed my Apple Watch wasn’t connecting either. Passkeys wouldn’t work properly, and the Bluetooth connection was just unreliable across the board. After searching through iOS settings without finding a solution, I took to Google, looking up variations of “Bluetooth disconnects after some time” and “AirPods Pro connect but fail after x minutes.” I tried all the typical fixes, like resetting network settings, turning off AirDrop, unpairing and repairing devices, and deleting devices to reduce the device count (though I wasn’t sure why that would help). Nothing seemed to work.

One thing that did have partial success was performing a full reboot of the phone. After a hard reboot, Bluetooth would function correctly for a while, but eventually, it would fail to connect again. This reboot seemed to reset something, but I wasn’t sure if it was a hardware or software issue.

I began to suspect it was a bug in iOS. I waited eagerly for each point release after 18.0, hoping the bug would be fixed, but no luck with any updates. At one point, I wondered if something in my home office environment was causing interference, but this theory was quickly discarded as the issue persisted with CarPlay in multiple vehicles and locations.

The issue was clearly related to the phone itself. By January, I was making more calls on my iPhone, and not having headphones was becoming a real problem. So, I decided to contact Apple Support. You might wonder why I didn’t reach out sooner. As I indicated, I don’t often use Bluetooth, it wasn’t a priority for me until now. Apple Support ran through the same troubleshooting steps I had already tried. They performed several diagnostics and confirmed that all hardware tests showed normal results. The representative acknowledged my frustration and offered a replacement. Normally, I’d have gone ahead with it, but I have several MFA tokens, and setting up a new phone sounded like a huge hassle. I told them I’d do more testing and asked for a follow-up call in a week to decide whether to proceed with a replacement.

Later that same day, while absentmindedly looking at my phone on my desk, a thought crossed my mind: could it be the case? The case I was using was a “CASEKOO Titanium 360° Rotatable Magnetic Stand for iPhone 16 Pro Max.” I had been happy with Casekoo cases for previous iPhones, so I did not hesitate to get this one.

I removed the case and tested my AirPods Pro. Success! When I checked the Bluetooth device list, I saw my Apple Watch was connected. I left the case off for the next two days and tested my various Bluetooth devices—everything worked perfectly. So, it turned out the case was causing the problem.

I then put the phone back in the case and tested it again. This time, Bluetooth worked fine, with no issues over several days.

I’m not sure if the phone was getting into a strange state while using inductive charging and removing it from the case fixed the issue, but I’m still testing it. I’ll update this if anything changes.

I’m posting this for anyone else who might be dealing with a similar issue.