How to play multiple footstep sounds without blocking animations? - swift

Question

Am coding a game with scenes that a man runs in different distance and durations. Due to different running speeds and durations(0.009sec, 0.02sec, 0.05sec...), it's not a good way to playing a sound with multiple steps inside. By now, It is set to play one step sound when footstep moves once.
I tried the following code:
Steps play one by one, but the animation thread blocked. Then man runs unsmoothly
DispatchQueue.main.async {
Sound.shared.play(.step)
}
The animation goes smoothly, but some step sounds missing, it could be two or more sounds play at the same time, so they sound like one step sound.
DispatchQueue.global(qos: .background).async {
Sound.shared.play(.step)
}
Same as the second
let soundQueue = DispatchQueue.init(label: "soundQueue", qos: .default, attributes: [.concurrent], autoreleaseFrequency: .inherit, target: nil)
soundQueue.async {
Sound.shared.play(.step)
}
Supplement Info: First 30 step sounds AVAudioPlayer are stored in an array so that sounds can be played in a fast way.
func playSound(_ type: SoundType) {
switch type {
case .key:
case .step:
self.doPlayStepSound()
//....
default:
break
}
var stepPlayerArr = [AVAudioPlayer?]()
func doPlayStepSound() {
if stepCount >= 30 {
stepCount = 0
}
if let player = stepPlayerArr[stepCount] {
player.play()
}
stepCount += 1
}
How can I play each step sound when the man's footstep moves without blocking the animations?
Thanks.