message: add an additional lookAhead to the onended callback
  this fixes an issue where the source was scheduled to stop in the time between the current time and the lookAhead time.
  fixes
diff: @@ -172,7 +172,8 @@ export abstract class OneShotSource<Options extends ToneAudioNodeOptions> extend
  const additionalTail = this._curve === "exponential" ? fadeOutTime * 2 : 0;
  this._stopSource(this.now() + additionalTail);
  this._onended();
  - }, this._stopTime - this.context.now());
  + // add an additional lookAhead to make sure that it's not unscheduled in the upcoming lookAhead interval
  + }, this._stopTime - this.context.now() + this.context.lookAhead);
  return this;
  }
  