<block>gr_udp_source</block>
<block>audio_source</block>
<block>gr_wavfile_source</block>
+ <block>gr_message_source</block>
<block>pad_source</block>
</cat>
<cat>
<block>gr_udp_sink</block>
<block>audio_sink</block>
<block>gr_wavfile_sink</block>
+ <block>gr_message_sink</block>
<block>pad_sink</block>
</cat>
<cat>