I'm getting the same error while running on simulator or actual device (Beta 8 and RC versions). In preview it works as expected.  "Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unacceptable type of value for to-one relationship: property = "linearity"; desired type = NSManagedObject; given type = NSManagedObject; value = <NSManagedObject: 0x281bc37f0>"

I just noticed I left out the first line in my code block above so here it is again in case someone sees this and is confused. let localFormattedTime = duration.formatted( .time(pattern: .minuteSecond(padMinuteToLength: 1)) .locale(.current) ) print(localFormattedTime) // prints: 1:15

Happened again, not sure why: let duration = Duration.seconds(75)

Same Problem on Instruments Version 15.1 (15C5042i). iPhone 15 Pro iOS 17.2 (21C5040g)