[Discuss-gnuradio] GFSK mod/demod does not work OK with wav file

<?xml version='1.0' encoding='utf-8'?>
<?grc format='1' created='3.7.11'?>
<flow_graph>
<timestamp>Fri May 12 16:01:07 2017</timestamp>
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<value>1.0</value>
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<value>True</value>
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<value>samp_rate*ss</value>
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<value></value>
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<value>0</value>
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<param>
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<value></value>
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<param>
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<value>False</value>
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<value></value>
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<value>True</value>
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<value>1024</value>
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<value>(941, 35)</value>
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<key>gui_hint</key>
<value></value>
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<param>
<key>_rotation</key>
<value>0</value>
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<value>False</value>
</param>
<param>
<key>id</key>
<value>qtgui_freq_sink_x_0</value>
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<param>
<key>legend</key>
<value>True</value>
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<param>
<key>alpha1</key>
<value>1.0</value>
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<param>
<key>color1</key>
<value>"blue"</value>
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<key>label1</key>
<value></value>
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<param>
<key>width1</key>
<value>1</value>
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<value>1.0</value>
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<param>
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<value>"dark blue"</value>
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<value></value>
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<value>1</value>
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<value>1.0</value>
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<value>"red"</value>
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<value></value>
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<value>1</value>
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<value>1.0</value>
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<value></value>
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<value>1</value>
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<value>1.0</value>
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<value>"black"</value>
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<value></value>
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<param>
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<value>1</value>
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<value>1.0</value>
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<param>
<key>color5</key>
<value>"cyan"</value>
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<key>label5</key>
<value></value>
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<param>
<key>width5</key>
<value>1</value>
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<value>1.0</value>
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<param>
<key>color6</key>
<value>"magenta"</value>
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<key>label6</key>
<value></value>
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<param>
<key>width6</key>
<value>1</value>
</param>
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<key>alpha7</key>
<value>1.0</value>
</param>
<param>
<key>color7</key>
<value>"yellow"</value>
</param>
<param>
<key>label7</key>
<value></value>
</param>
<param>
<key>width7</key>
<value>1</value>
</param>
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<value>1.0</value>
</param>
<param>
<key>color8</key>
<value>"dark red"</value>
</param>
<param>
<key>label8</key>
<value></value>
</param>
<param>
<key>width8</key>
<value>1</value>
</param>
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<value>1.0</value>
</param>
<param>
<key>color9</key>
<value>"dark green"</value>
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<param>
<key>label9</key>
<value></value>
</param>
<param>
<key>width9</key>
<value>1</value>
</param>
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<value>0</value>
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<value>0</value>
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<value>""</value>
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<param>
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<value>1</value>
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<param>
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<value>True</value>
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<param>
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<value>True</value>
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<value>0</value>
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<param>
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<value>0.0</value>
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<param>
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<value>qtgui.TRIG_MODE_FREE</value>
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<param>
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<value>""</value>
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<param>
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<value>float</value>
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<param>
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<value>0.10</value>
</param>
<param>
<key>wintype</key>
<value>firdes.WIN_BLACKMAN_hARRIS</value>
</param>
<param>
<key>label</key>
<value>Relative Gain</value>
</param>
<param>
<key>ymax</key>
<value>10</value>
</param>
<param>
<key>ymin</key>
<value>-140</value>
</param>
<param>
<key>units</key>
<value>dB</value>
</param>
</block>
<block>
<key>qtgui_freq_sink_x</key>
<param>
<key>autoscale</key>
<value>False</value>
</param>
<param>
<key>average</key>
<value>1.0</value>
</param>
<param>
<key>axislabels</key>
<value>True</value>
</param>
<param>
<key>bw</key>
<value>samp_rate</value>
</param>
<param>
<key>alias</key>
<value></value>
</param>
<param>
<key>fc</key>
<value>0</value>
</param>
<param>
<key>comment</key>
<value></value>
</param>
<param>
<key>ctrlpanel</key>
<value>False</value>
</param>
<param>
<key>affinity</key>
<value></value>
</param>
<param>
<key>_enabled</key>
<value>True</value>
</param>
<param>
<key>fftsize</key>
<value>1024</value>
</param>
<param>
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<value>(1061, 203)</value>
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<param>
<key>gui_hint</key>
<value></value>
</param>
<param>
<key>_rotation</key>
<value>0</value>
</param>
<param>
<key>grid</key>
<value>False</value>
</param>
<param>
<key>id</key>
<value>qtgui_freq_sink_x_1</value>
</param>
<param>
<key>legend</key>
<value>True</value>
</param>
<param>
<key>alpha1</key>
<value>1.0</value>
</param>
<param>
<key>color1</key>
<value>"blue"</value>
</param>
<param>
<key>label1</key>
<value></value>
</param>
<param>
<key>width1</key>
<value>1</value>
</param>
<param>
<key>alpha10</key>
<value>1.0</value>
</param>
<param>
<key>color10</key>
<value>"dark blue"</value>
</param>
<param>
<key>label10</key>
<value></value>
</param>
<param>
<key>width10</key>
<value>1</value>
</param>
<param>
<key>alpha2</key>
<value>1.0</value>
</param>
<param>
<key>color2</key>
<value>"red"</value>
</param>
<param>
<key>label2</key>
<value></value>
</param>
<param>
<key>width2</key>
<value>1</value>
</param>
<param>
<key>alpha3</key>
<value>1.0</value>
</param>
<param>
<key>color3</key>
<value>"green"</value>
</param>
<param>
<key>label3</key>
<value></value>
</param>
<param>
<key>width3</key>
<value>1</value>
</param>
<param>
<key>alpha4</key>
<value>1.0</value>
</param>
<param>
<key>color4</key>
<value>"black"</value>
</param>
<param>
<key>label4</key>
<value></value>
</param>
<param>
<key>width4</key>
<value>1</value>
</param>
<param>
<key>alpha5</key>
<value>1.0</value>
</param>
<param>
<key>color5</key>
<value>"cyan"</value>
</param>
<param>
<key>label5</key>
<value></value>
</param>
<param>
<key>width5</key>
<value>1</value>
</param>
<param>
<key>alpha6</key>
<value>1.0</value>
</param>
<param>
<key>color6</key>
<value>"magenta"</value>
</param>
<param>
<key>label6</key>
<value></value>
</param>
<param>
<key>width6</key>
<value>1</value>
</param>
<param>
<key>alpha7</key>
<value>1.0</value>
</param>
<param>
<key>color7</key>
<value>"yellow"</value>
</param>
<param>
<key>label7</key>
<value></value>
</param>
<param>
<key>width7</key>
<value>1</value>
</param>
<param>
<key>alpha8</key>
<value>1.0</value>
</param>
<param>
<key>color8</key>
<value>"dark red"</value>
</param>
<param>
<key>label8</key>
<value></value>
</param>
<param>
<key>width8</key>
<value>1</value>
</param>
<param>
<key>alpha9</key>
<value>1.0</value>
</param>
<param>
<key>color9</key>
<value>"dark green"</value>
</param>
<param>
<key>label9</key>
<value></value>
</param>
<param>
<key>width9</key>
<value>1</value>
</param>
<param>
<key>maxoutbuf</key>
<value>0</value>
</param>
<param>
<key>minoutbuf</key>
<value>0</value>
</param>
<param>
<key>name</key>
<value>"Output"</value>
</param>
<param>
<key>nconnections</key>
<value>1</value>
</param>
<param>
<key>showports</key>
<value>True</value>
</param>
<param>
<key>freqhalf</key>
<value>True</value>
</param>
<param>
<key>tr_chan</key>
<value>0</value>
</param>
<param>
<key>tr_level</key>
<value>0.0</value>
</param>
<param>
<key>tr_mode</key>
<value>qtgui.TRIG_MODE_FREE</value>
</param>
<param>
<key>tr_tag</key>
<value>""</value>
</param>
<param>
<key>type</key>
<value>float</value>
</param>
<param>
<key>update_time</key>
<value>0.10</value>
</param>
<param>
<key>wintype</key>
<value>firdes.WIN_BLACKMAN_hARRIS</value>
</param>
<param>
<key>label</key>
<value>Relative Gain</value>
</param>
<param>
<key>ymax</key>
<value>10</value>
</param>
<param>
<key>ymin</key>
<value>-140</value>
</param>
<param>
<key>units</key>
<value>dB</value>
</param>
</block>
<block>
<key>qtgui_freq_sink_x</key>
<param>
<key>autoscale</key>
<value>False</value>
</param>
<param>
<key>average</key>
<value>1.0</value>
</param>
<param>
<key>axislabels</key>
<value>True</value>
</param>
<param>
<key>bw</key>
<value>samp_rate</value>
</param>
<param>
<key>alias</key>
<value></value>
</param>
<param>
<key>fc</key>
<value>0</value>
</param>
<param>
<key>comment</key>
<value></value>
</param>
<param>
<key>ctrlpanel</key>
<value>False</value>
</param>
<param>
<key>affinity</key>
<value></value>
</param>
<param>
<key>_enabled</key>
<value>True</value>
</param>
<param>
<key>fftsize</key>
<value>1024</value>
</param>
<param>
<key>_coordinate</key>
<value>(351, 327)</value>
</param>
<param>
<key>gui_hint</key>
<value></value>
</param>
<param>
<key>_rotation</key>
<value>0</value>
</param>
<param>
<key>grid</key>
<value>False</value>
</param>
<param>
<key>id</key>
<value>qtgui_freq_sink_x_2</value>
</param>
<param>
<key>legend</key>
<value>True</value>
</param>
<param>
<key>alpha1</key>
<value>1.0</value>
</param>
<param>
<key>color1</key>
<value>"blue"</value>
</param>
<param>
<key>label1</key>
<value></value>
</param>
<param>
<key>width1</key>
<value>1</value>
</param>
<param>
<key>alpha10</key>
<value>1.0</value>
</param>
<param>
<key>color10</key>
<value>"dark blue"</value>
</param>
<param>
<key>label10</key>
<value></value>
</param>
<param>
<key>width10</key>
<value>1</value>
</param>
<param>
<key>alpha2</key>
<value>1.0</value>
</param>
<param>
<key>color2</key>
<value>"red"</value>
</param>
<param>
<key>label2</key>
<value></value>
</param>
<param>
<key>width2</key>
<value>1</value>
</param>
<param>
<key>alpha3</key>
<value>1.0</value>
</param>
<param>
<key>color3</key>
<value>"green"</value>
</param>
<param>
<key>label3</key>
<value></value>
</param>
<param>
<key>width3</key>
<value>1</value>
</param>
<param>
<key>alpha4</key>
<value>1.0</value>
</param>
<param>
<key>color4</key>
<value>"black"</value>
</param>
<param>
<key>label4</key>
<value></value>
</param>
<param>
<key>width4</key>
<value>1</value>
</param>
<param>
<key>alpha5</key>
<value>1.0</value>
</param>
<param>
<key>color5</key>
<value>"cyan"</value>
</param>
<param>
<key>label5</key>
<value></value>
</param>
<param>
<key>width5</key>
<value>1</value>
</param>
<param>
<key>alpha6</key>
<value>1.0</value>
</param>
<param>
<key>color6</key>
<value>"magenta"</value>
</param>
<param>
<key>label6</key>
<value></value>
</param>
<param>
<key>width6</key>
<value>1</value>
</param>
<param>
<key>alpha7</key>
<value>1.0</value>
</param>
<param>
<key>color7</key>
<value>"yellow"</value>
</param>
<param>
<key>label7</key>
<value></value>
</param>
<param>
<key>width7</key>
<value>1</value>
</param>
<param>
<key>alpha8</key>
<value>1.0</value>
</param>
<param>
<key>color8</key>
<value>"dark red"</value>
</param>
<param>
<key>label8</key>
<value></value>
</param>
<param>
<key>width8</key>
<value>1</value>
</param>
<param>
<key>alpha9</key>
<value>1.0</value>
</param>
<param>
<key>color9</key>
<value>"dark green"</value>
</param>
<param>
<key>label9</key>
<value></value>
</param>
<param>
<key>width9</key>
<value>1</value>
</param>
<param>
<key>maxoutbuf</key>
<value>0</value>
</param>
<param>
<key>minoutbuf</key>
<value>0</value>
</param>
<param>
<key>name</key>
<value>"Source"</value>
</param>
<param>
<key>nconnections</key>
<value>1</value>
</param>
<param>
<key>showports</key>
<value>True</value>
</param>
<param>
<key>freqhalf</key>
<value>True</value>
</param>
<param>
<key>tr_chan</key>
<value>0</value>
</param>
<param>
<key>tr_level</key>
<value>0.0</value>
</param>
<param>
<key>tr_mode</key>
<value>qtgui.TRIG_MODE_FREE</value>
</param>
<param>
<key>tr_tag</key>
<value>""</value>
</param>
<param>
<key>type</key>
<value>float</value>
</param>
<param>
<key>update_time</key>
<value>0.10</value>
</param>
<param>
<key>wintype</key>
<value>firdes.WIN_BLACKMAN_hARRIS</value>
</param>
<param>
<key>label</key>
<value>Relative Gain</value>
</param>
<param>
<key>ymax</key>
<value>10</value>
</param>
<param>
<key>ymin</key>
<value>-140</value>
</param>
<param>
<key>units</key>
<value>dB</value>
</param>
</block>
<connection>
<source_block_id>analog_quadrature_demod_cf_0</source_block_id>
<sink_block_id>qtgui_freq_sink_x_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>analog_sig_source_x_0</source_block_id>
<sink_block_id>blocks_throttle_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>blks2_packet_decoder_0</source_block_id>
<sink_block_id>audio_sink_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>blks2_packet_decoder_0</source_block_id>
<sink_block_id>qtgui_freq_sink_x_1</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>blks2_packet_encoder_0</source_block_id>
<sink_block_id>digital_gfsk_mod_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>blocks_throttle_0</source_block_id>
<sink_block_id>blks2_packet_encoder_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>blocks_throttle_0</source_block_id>
<sink_block_id>qtgui_freq_sink_x_2</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>blocks_wavfile_source_0</source_block_id>
<sink_block_id>blocks_throttle_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>digital_gfsk_demod_0</source_block_id>
<sink_block_id>blks2_packet_decoder_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>digital_gfsk_mod_0</source_block_id>
<sink_block_id>analog_quadrature_demod_cf_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
<connection>
<source_block_id>digital_gfsk_mod_0</source_block_id>
<sink_block_id>digital_gfsk_demod_0</sink_block_id>
<source_key>0</source_key>
<sink_key>0</sink_key>
</connection>
</flow_graph>

I'm playing with a GFSK modulator demodulator from here:

https://www.scribd.com/doc/254559988/Gaussian-Frequency-shift-Keying-With-GNU-Radio

It works fine when transmitting a cosine, but when I transmit a audio
signal (everything the same) it sounds bad, with noise and intermittent
sound.

What am I doing wrong?



regards