code: function shift (size) {
  		size = size || samplesPerFrame;
  
  		//if still empty - return existing buffer
  		if (isEmpty) return data;
  
  		let output = data.slice(0, size)
  
  		data.consume(size)
  
  		//if size is too small, fill with silence
  		if (output.length < size) {
  			output = util.pad(output, size)
  		}
  
  		return output;
  	}
docs: get last ready data