AudioPlaybackTrack forces unwanted polyphony and bypasses AudioStreamPlayer3D's max_polyphony limit.

[KnightNine]

Godot version

4.X

System information

Windows 10

Issue description

I have a looping animation, I want the sound (AudioPlaybackTrack) within that animation to loop when the animation loops.
But if the end_offset of the audio clip exists outside the animation length the audio is not stopped and then overlaps with itself, and it it's practically impossible to set the end_offset to the very end of the animation length.
(Because the adjusting end_offset value manually to get the exact endpoint of the animation using the sound length and the animation length values is finnicky. I also can't snap the end offset to anything by dragging it in the timeline either.)

That aside, this sound overlapping shouldn't even happen anyways if the max_polyphony property of the AudioStreamPlayer3D being used by the audio track is set to 1. It should only be able to play one sound at a time so it should cut the last sound being played when the loop restarts to begin the sound again.

---

Note:

When the AudioPlaybackTrack makes the AudioStreamPlayer3D play a sound it creates and adds an "AudioStreamPolyphonic" resource to it, I assume that this resource ignores the max_polyphony property of the AudioStreamPlayer.

Steps to reproduce

• create an AudioStreamPlayer3D and an AnimationPlayer in your scene.
• create an animation and select the looping button.
• add an Audio Playback Track to it that is connected to the AudioStreamPlayer3D
• import and add a sound file to the Audio Playback Track that is longer than the length of the animation
• set AudioStreamPlayer3D max_polyphony to 1
• play the animation.

The audio should continue to play and overlap with itself even after the loop ends.

Minimal reproduction project

To be added if necessary.

[TokageItLab]

Is it just an AudioPlaybackTrack issue, or does this issue also occur when using AudioStreamPolyphonic directly? It is needed to isolate the problem.

If it is the latter, I think it is more of an audio side issue, since on the AnimationMixer side we have set audio_max_polyphony for the audio stream.

In any case, it needs to be tested.

[KnightNine]

@TokageItLab
tested this code, the issue relates to the AudioStreamPolyphonic directly:

@onready var player:AudioStreamPlayer = get_node("AudioStreamPlayer")
@onready var sound = preload("res://Objective Beam Idle.ogg")
@onready var sound2 = preload("res://Hiss.ogg")


func _ready():
	player.stream = AudioStreamPolyphonic.new()
	player.playing = true
	await get_tree().create_timer(1).timeout
	
	
	print(player.stream)
	var playback = player.get_stream_playback() as AudioStreamPlaybackPolyphonic
	var id = playback.play_stream(sound)
	await get_tree().create_timer(1).timeout
	var id2 = playback.play_stream(sound2) # 1 second later, start another clip
	await get_tree().create_timer(1).timeout
	

max_polyphony is ignored by AudioStreamPolyphonic

[MJacred]

@KnightNine: could you test #86054, please? Your issue of accidental sound overlapping reminds me of #86053

[KnightNine]

@MJacred Tested #86054 , the issue persists.

[KnightNine]

Just wondering how do I add looping audio to a looping animation (like an in game generator or radio where the noise needs to be constant) if this functionality doesn't work? Is there a workaround in 4.2 or 4.3?