Is there such a thing as a bum IPhone 16?

Definitely make an appointment and Apple can run diagnostics on the device. It is not out of the realm of possibility to have a defective device and you have a free year of AppleCare in case there is anything wrong.

Genius Bar Reservation and Apple Support Options - Apple

You purchased the iPhone 16 just 3 days ago. Your iPhone is covered under Apple’s 1YR limited warranty. You have two solid choices:

1. Return the iPhone for a full refund and then purchase a replacement since you have 14 days to return your iPhone. OR
2. Take advantage of the warranty and contact 👉 Official Apple Support OR you can always get your iPhone examined at the Apple Store 👉 Genius Bar Reservation and Apple Support Options or at an Authorized Service Center for further diagnosis and evaluation.

Axel F.

"Is there such a thing as a bum IPhone 16?: I’ve updated my new 16 to IOS 18.2. Audio in apps seems to come and go and even Siri is sometimes there and sometimes not. This isn’t making any sense and I’ve only had the phone for three days"

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iOS18 Issues:

A. See here: Recording snap stories and voice memos on… - Apple Community

B. Troubleshooting CarPlay with Low Volume:

Seems to be catching on. Question is: "Just how many people have actually reported this to Apple?" Apple barely reads these forums as it is on their own time and will. So,…

C. Report this as a Bug to Apple...

Do your Part: Provide Apple with feedback on this, letting them know about this issue.  Apple may not get back to you directly, but the more feedback they receive on this, the more they will know what is occurring, and what bug fixes to include in updates to come. Apple will know nothing of this, if you don't report it to them.

1. Go Here: Feedback - iPhone - Apple
2. Select: "Bug Report" for the "Feedback Type"
3. Comment: that this all began after installing an update. Include the URL of this thread
4. Proceed from there as necessary