Apple already encrypts the actual recordings, but with iOS 17, iPadOS 17, and macOS Sonoma, the titles will be encrypted too, according to an Apple support document (via MacRumors).

As a result, Voice Memo titles on devices that haven’t been updated to those operating systems might look a little unusual. Per Apple:

Because of this additional encryption, when you update one of your Apple devices to iOS 17, iPadOS 17, or macOS Sonoma, your devices that you haven’t yet updated—with older versions of Voice Memos—may display the date and time of the recording (for example, “2023-08-11T07:53:31Z”) as the title, rather than the previous title of the recording.