message: Part can accept any object-like thing with a 'time' property
diff: @@ -215,7 +215,7 @@ export class Part<ValueType = any> extends ToneEvent<ValueType> {
  add(time: Time, value?: any): this;
  add(time: Time | object, value?: any): this {
  // extract the parameters
  - if (isObject(time) && time.hasOwnProperty("time")) {
  + if (time instanceof Object && time.hasOwnProperty("time")) {
  value = time;
  time = value.time;
  }
  