add checks for detune on audio buffer for safari (fixes #15566)

Author: ngokevin

src/audio/Audio.js

@@ -95,7 +95,13 @@ Audio.prototype = Object.assign( Object.create( Object3D.prototype ), {
 		var source = this.context.createBufferSource();
 
 		source.buffer = this.buffer;
-		source.detune.value = this.detune;
+
+		if ( source.detune ) {
+
+			source.detune.value = this.detune;
+
+		}
+
 		source.loop = this.loop;
 		source.onended = this.onEnded.bind( this );
 		source.playbackRate.setValueAtTime( this.playbackRate, this.startTime );
@@ -228,6 +234,8 @@ Audio.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 		this.detune = value;
 
+		if ( !this.source.detune ) return;
+
 		if ( this.isPlaying === true ) {
 
 			this.source.detune.setTargetAtTime( this.detune, this.context.currentTime, 0.01 );