         oscillator.originalFrequency = frequency
         oscillator.nofg = nofg
         oscillator.frequency.cancelScheduledValues now
-        oscillator.frequency.setTargetAtTime frequency * @parameters.octave * Audio.CUR_OCTAVE[Audio.OCTAVE_STEP], 0, @parameters.portamento / 1000.0
+        oscillator.frequency.setTargetAtTime frequency * @parameters.octave * Audio.CUR_OCTAVE[Audio.OCTAVE_STEP], 0, @parameters.portamento / 1000.0 || 0.001
         oscillator.detune.setValueAtTime @parameters.detune, 0
         oscillator.connect nofg
         oscillator.start now

                null
            else
                @activeOscillators[0].frequency.cancelScheduledValues now
                @activeOscillators[0].frequency.setTargetAtTime @active[@active.length-1] * @parameters.octave, 0, @parameters.portamento / 1000
        null

    @property 'type',

        else
            # frequency
            @activeOscillators[0].frequency.cancelScheduledValues now
            @activeOscillators[0].frequency.setTargetAtTime frequency * @parameters.octave * Audio.CUR_OCTAVE[Audio.OCTAVE_STEP], 0, @parameters.portamento / 1000.0 || 0.001
        null

    stop: (frequency) ->
