<figure {{ with .Get "class" }}class="{{ . }}"{{ end }}>
  <audio controls preload="{{ .Get "preload" | default "metadata" }}">
    {{ with .Get "src" }}<source src="{{ . | relURL }}" type="audio/mpeg">{{ end }}
  </audio>
  {{ with .Get "caption" }}<figcaption class="audioCaption">{{ . }}</figcaption>{{ end }}
</figure>