IOS: 0 timing or delayed execution of error or minimum error?

The problem is as follows:

Rhythm games require a lot of action related to the rhythm of the music, and in order to maintain the rhythm, it is necessary to have a close relationship with the beat. The interval requirement cannot exceed 0.02 seconds or less.

The Asyncafter (Deadline:) method in GCD is currently used, but the error is always greater than 0.05 seconds, and there is no guarantee that the error will pass. Is there a better way to solve the error?

var time = Date().timeIntervalSince1970let dq = DispatchQueue(label: "queue", qos: .userInitiated, attributes: [.concurrent, .initiallyInactive])            dq.async {                self.audioPlayer.play()                time = Date().timeIntervalSince1970            }            dq.asyncAfter(deadline: .now() + 0.43, execute: {                let res = Date().timeIntervalSince1970                print(" 误差： \(res - time)")                            })

The following is a multiple-run console print result (this number refers to the actual interval, which is far from 0.43 of the expected interval and is not stable):

IOS: 0 timing or delayed execution of error or minimum error? >> iOS

The answer is quite clear:
Http://www.goodpm.net/postreply/ios/1010000008928622/iOS 0 Timing or delay execution of error or minimum error. html

IOS: 0 timing or delayed execution of error or minimum error?