diff --git a/demos/gnuradio/hackrf_file_tx_demo.grc b/demos/gnuradio/hackrf_file_tx_demo.grc
index 37c7721..59d7f38 100644
--- a/demos/gnuradio/hackrf_file_tx_demo.grc
+++ b/demos/gnuradio/hackrf_file_tx_demo.grc
@@ -49,7 +49,7 @@ blocks:
   id: variable
   parameters:
     comment: ''
-    value: '931937500'
+    value: '929937500'
   states:
     bus_sink: false
     bus_source: false
@@ -242,285 +242,44 @@ blocks:
     coordinate: [200, 12.0]
     rotation: 0
     state: true
-- name: osmosdr_sink_0
-  id: osmosdr_sink
+- name: rational_resampler_xxx_0
+  id: rational_resampler_xxx
   parameters:
     affinity: ''
     alias: ''
-    ant0: '1'
-    ant1: ''
-    ant10: ''
-    ant11: ''
-    ant12: ''
-    ant13: ''
-    ant14: ''
-    ant15: ''
-    ant16: ''
-    ant17: ''
-    ant18: ''
-    ant19: ''
-    ant2: ''
-    ant20: ''
-    ant21: ''
-    ant22: ''
-    ant23: ''
-    ant24: ''
-    ant25: ''
-    ant26: ''
-    ant27: ''
-    ant28: ''
-    ant29: ''
-    ant3: ''
-    ant30: ''
-    ant31: ''
-    ant4: ''
-    ant5: ''
-    ant6: ''
-    ant7: ''
-    ant8: ''
-    ant9: ''
-    args: hackrf=0
-    bb_gain0: '20'
-    bb_gain1: '20'
-    bb_gain10: '20'
-    bb_gain11: '20'
-    bb_gain12: '20'
-    bb_gain13: '20'
-    bb_gain14: '20'
-    bb_gain15: '20'
-    bb_gain16: '20'
-    bb_gain17: '20'
-    bb_gain18: '20'
-    bb_gain19: '20'
-    bb_gain2: '20'
-    bb_gain20: '20'
-    bb_gain21: '20'
-    bb_gain22: '20'
-    bb_gain23: '20'
-    bb_gain24: '20'
-    bb_gain25: '20'
-    bb_gain26: '20'
-    bb_gain27: '20'
-    bb_gain28: '20'
-    bb_gain29: '20'
-    bb_gain3: '20'
-    bb_gain30: '20'
-    bb_gain31: '20'
-    bb_gain4: '20'
-    bb_gain5: '20'
-    bb_gain6: '20'
-    bb_gain7: '20'
-    bb_gain8: '20'
-    bb_gain9: '20'
-    bw0: '0'
-    bw1: '0'
-    bw10: '0'
-    bw11: '0'
-    bw12: '0'
-    bw13: '0'
-    bw14: '0'
-    bw15: '0'
-    bw16: '0'
-    bw17: '0'
-    bw18: '0'
-    bw19: '0'
-    bw2: '0'
-    bw20: '0'
-    bw21: '0'
-    bw22: '0'
-    bw23: '0'
-    bw24: '0'
-    bw25: '0'
-    bw26: '0'
-    bw27: '0'
-    bw28: '0'
-    bw29: '0'
-    bw3: '0'
-    bw30: '0'
-    bw31: '0'
-    bw4: '0'
-    bw5: '0'
-    bw6: '0'
-    bw7: '0'
-    bw8: '0'
-    bw9: '0'
-    clock_source0: ''
-    clock_source1: ''
-    clock_source2: ''
-    clock_source3: ''
-    clock_source4: ''
-    clock_source5: ''
-    clock_source6: ''
-    clock_source7: ''
     comment: ''
-    corr0: '0.8'
-    corr1: '0'
-    corr10: '0'
-    corr11: '0'
-    corr12: '0'
-    corr13: '0'
-    corr14: '0'
-    corr15: '0'
-    corr16: '0'
-    corr17: '0'
-    corr18: '0'
-    corr19: '0'
-    corr2: '0'
-    corr20: '0'
-    corr21: '0'
-    corr22: '0'
-    corr23: '0'
-    corr24: '0'
-    corr25: '0'
-    corr26: '0'
-    corr27: '0'
-    corr28: '0'
-    corr29: '0'
-    corr3: '0'
-    corr30: '0'
-    corr31: '0'
-    corr4: '0'
-    corr5: '0'
-    corr6: '0'
-    corr7: '0'
-    corr8: '0'
-    corr9: '0'
-    freq0: center_freq
-    freq1: 100e6
-    freq10: 100e6
-    freq11: 100e6
-    freq12: 100e6
-    freq13: 100e6
-    freq14: 100e6
-    freq15: 100e6
-    freq16: 100e6
-    freq17: 100e6
-    freq18: 100e6
-    freq19: 100e6
-    freq2: 100e6
-    freq20: 100e6
-    freq21: 100e6
-    freq22: 100e6
-    freq23: 100e6
-    freq24: 100e6
-    freq25: 100e6
-    freq26: 100e6
-    freq27: 100e6
-    freq28: 100e6
-    freq29: 100e6
-    freq3: 100e6
-    freq30: 100e6
-    freq31: 100e6
-    freq4: 100e6
-    freq5: 100e6
-    freq6: 100e6
-    freq7: 100e6
-    freq8: 100e6
-    freq9: 100e6
-    gain0: '40'
-    gain1: '10'
-    gain10: '10'
-    gain11: '10'
-    gain12: '10'
-    gain13: '10'
-    gain14: '10'
-    gain15: '10'
-    gain16: '10'
-    gain17: '10'
-    gain18: '10'
-    gain19: '10'
-    gain2: '10'
-    gain20: '10'
-    gain21: '10'
-    gain22: '10'
-    gain23: '10'
-    gain24: '10'
-    gain25: '10'
-    gain26: '10'
-    gain27: '10'
-    gain28: '10'
-    gain29: '10'
-    gain3: '10'
-    gain30: '10'
-    gain31: '10'
-    gain4: '10'
-    gain5: '10'
-    gain6: '10'
-    gain7: '10'
-    gain8: '10'
-    gain9: '10'
-    if_gain0: '20'
-    if_gain1: '20'
-    if_gain10: '20'
-    if_gain11: '20'
-    if_gain12: '20'
-    if_gain13: '20'
-    if_gain14: '20'
-    if_gain15: '20'
-    if_gain16: '20'
-    if_gain17: '20'
-    if_gain18: '20'
-    if_gain19: '20'
-    if_gain2: '20'
-    if_gain20: '20'
-    if_gain21: '20'
-    if_gain22: '20'
-    if_gain23: '20'
-    if_gain24: '20'
-    if_gain25: '20'
-    if_gain26: '20'
-    if_gain27: '20'
-    if_gain28: '20'
-    if_gain29: '20'
-    if_gain3: '20'
-    if_gain30: '20'
-    if_gain31: '20'
-    if_gain4: '20'
-    if_gain5: '20'
-    if_gain6: '20'
-    if_gain7: '20'
-    if_gain8: '20'
-    if_gain9: '20'
+    decim: int(samp_rate // math.gcd(int(hw_rate), int(samp_rate)))
+    fbw: '0'
+    interp: int(hw_rate // math.gcd(int(hw_rate), int(samp_rate)))
     maxoutbuf: '0'
     minoutbuf: '0'
-    nchan: '1'
-    num_mboards: '1'
-    sample_rate: hw_rate
-    sync: sync
-    time_source0: ''
-    time_source1: ''
-    time_source2: ''
-    time_source3: ''
-    time_source4: ''
-    time_source5: ''
-    time_source6: ''
-    time_source7: ''
-    type: fc32
+    taps: '[]'
+    type: ccc
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [928, 460.0]
+    coordinate: [1152, 252.0]
     rotation: 0
-    state: true
-- name: rational_resampler_xxx_0
-  id: rational_resampler_xxx
+    state: enabled
+- name: soapy_hackrf_sink_0
+  id: soapy_hackrf_sink
   parameters:
     affinity: ''
     alias: ''
+    amp: 'False'
+    bandwidth: '0'
+    center_freq: center_freq
     comment: ''
-    decim: int(samp_rate // math.gcd(int(hw_rate), int(samp_rate)))
-    fbw: '0'
-    interp: int(hw_rate // math.gcd(int(hw_rate), int(samp_rate)))
-    maxoutbuf: '0'
-    minoutbuf: '0'
-    taps: '[]'
-    type: ccc
+    dev_args: ''
+    samp_rate: hw_rate
+    type: fc32
+    vga: '28'
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1152, 252.0]
+    coordinate: [1152, 368.0]
     rotation: 0
     state: enabled
 
@@ -532,7 +291,7 @@ connections:
 - [blocks_throttle_0, '0', rational_resampler_xxx_0, '0']
 - [blocks_uchar_to_float_0, '0', blocks_add_const_vxx_0, '0']
 - [blocks_unpack_k_bits_bb_0, '0', blocks_repeat_0, '0']
-- [rational_resampler_xxx_0, '0', osmosdr_sink_0, '0']
+- [rational_resampler_xxx_0, '0', soapy_hackrf_sink_0, '0']
 
 metadata:
   file_format: 1
diff --git a/demos/gnuradio/hackrf_file_tx_demo_osmosdr_sink.grc b/demos/gnuradio/hackrf_file_tx_demo_osmosdr_sink.grc
new file mode 100644
index 0000000..37c7721
--- /dev/null
+++ b/demos/gnuradio/hackrf_file_tx_demo_osmosdr_sink.grc
@@ -0,0 +1,539 @@
+options:
+  parameters:
+    author: ''
+    catch_exceptions: 'True'
+    category: '[GRC Hier Blocks]'
+    cmake_opt: ''
+    comment: ''
+    copyright: ''
+    description: ''
+    gen_cmake: 'On'
+    gen_linking: dynamic
+    generate_options: no_gui
+    hier_block_src_path: '.:'
+    id: hackrf_file_tx_demo
+    max_nouts: '0'
+    output_language: python
+    placement: (0,0)
+    qt_qss_theme: ''
+    realtime_scheduling: ''
+    run: 'True'
+    run_command: '{python} -u {filename}'
+    run_options: run
+    sizing_mode: fixed
+    thread_safe_setters: ''
+    title: HackRF FLEX File TX Demo
+    window_size: (1000,1000)
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [8, 12.0]
+    rotation: 0
+    state: enabled
+
+blocks:
+- name: baud_rate
+  id: variable
+  parameters:
+    comment: ''
+    value: '1600'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [296, 12.0]
+    rotation: 0
+    state: enabled
+- name: center_freq
+  id: variable
+  parameters:
+    comment: ''
+    value: '931937500'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [728, 12.0]
+    rotation: 0
+    state: enabled
+- name: deviation
+  id: variable
+  parameters:
+    comment: ''
+    value: '4800'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [640, 12.0]
+    rotation: 0
+    state: enabled
+- name: hw_rate
+  id: variable
+  parameters:
+    comment: ''
+    value: '2000000'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [480, 12.0]
+    rotation: 0
+    state: enabled
+- name: samp_rate
+  id: variable
+  parameters:
+    comment: ''
+    value: sps * baud_rate
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [384, 12.0]
+    rotation: 0
+    state: enabled
+- name: sps
+  id: variable
+  parameters:
+    comment: ''
+    value: '100'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [560, 12.0]
+    rotation: 0
+    state: enabled
+- name: analog_frequency_modulator_fc_0
+  id: analog_frequency_modulator_fc
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    sensitivity: 2 * math.pi * deviation / samp_rate
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [784, 276.0]
+    rotation: 0
+    state: true
+- name: blocks_add_const_vxx_0
+  id: blocks_add_const_vxx
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    const: '-0.5'
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    type: float
+    vlen: '1'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [616, 276.0]
+    rotation: 0
+    state: true
+- name: blocks_file_source_0
+  id: blocks_file_source
+  parameters:
+    affinity: ''
+    alias: ''
+    begin_tag: pmt.PMT_NIL
+    comment: ''
+    file: encoded.bin
+    length: '0'
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    offset: '0'
+    repeat: 'False'
+    type: byte
+    vlen: '1'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [88, 148.0]
+    rotation: 0
+    state: true
+- name: blocks_repeat_0
+  id: blocks_repeat
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    interp: sps
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    type: byte
+    vlen: '1'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [264, 276.0]
+    rotation: 0
+    state: true
+- name: blocks_throttle_0
+  id: blocks_throttle
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    ignoretag: 'True'
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    samples_per_second: samp_rate
+    type: complex
+    vlen: '1'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [976, 276.0]
+    rotation: 0
+    state: true
+- name: blocks_uchar_to_float_0
+  id: blocks_uchar_to_float
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    maxoutbuf: '0'
+    minoutbuf: '0'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [448, 280.0]
+    rotation: 0
+    state: true
+- name: blocks_unpack_k_bits_bb_0
+  id: blocks_unpack_k_bits_bb
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    k: '8'
+    maxoutbuf: '0'
+    minoutbuf: '0'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [96, 276.0]
+    rotation: 0
+    state: true
+- name: import_0
+  id: import
+  parameters:
+    alias: ''
+    comment: ''
+    imports: import math
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [200, 12.0]
+    rotation: 0
+    state: true
+- name: osmosdr_sink_0
+  id: osmosdr_sink
+  parameters:
+    affinity: ''
+    alias: ''
+    ant0: '1'
+    ant1: ''
+    ant10: ''
+    ant11: ''
+    ant12: ''
+    ant13: ''
+    ant14: ''
+    ant15: ''
+    ant16: ''
+    ant17: ''
+    ant18: ''
+    ant19: ''
+    ant2: ''
+    ant20: ''
+    ant21: ''
+    ant22: ''
+    ant23: ''
+    ant24: ''
+    ant25: ''
+    ant26: ''
+    ant27: ''
+    ant28: ''
+    ant29: ''
+    ant3: ''
+    ant30: ''
+    ant31: ''
+    ant4: ''
+    ant5: ''
+    ant6: ''
+    ant7: ''
+    ant8: ''
+    ant9: ''
+    args: hackrf=0
+    bb_gain0: '20'
+    bb_gain1: '20'
+    bb_gain10: '20'
+    bb_gain11: '20'
+    bb_gain12: '20'
+    bb_gain13: '20'
+    bb_gain14: '20'
+    bb_gain15: '20'
+    bb_gain16: '20'
+    bb_gain17: '20'
+    bb_gain18: '20'
+    bb_gain19: '20'
+    bb_gain2: '20'
+    bb_gain20: '20'
+    bb_gain21: '20'
+    bb_gain22: '20'
+    bb_gain23: '20'
+    bb_gain24: '20'
+    bb_gain25: '20'
+    bb_gain26: '20'
+    bb_gain27: '20'
+    bb_gain28: '20'
+    bb_gain29: '20'
+    bb_gain3: '20'
+    bb_gain30: '20'
+    bb_gain31: '20'
+    bb_gain4: '20'
+    bb_gain5: '20'
+    bb_gain6: '20'
+    bb_gain7: '20'
+    bb_gain8: '20'
+    bb_gain9: '20'
+    bw0: '0'
+    bw1: '0'
+    bw10: '0'
+    bw11: '0'
+    bw12: '0'
+    bw13: '0'
+    bw14: '0'
+    bw15: '0'
+    bw16: '0'
+    bw17: '0'
+    bw18: '0'
+    bw19: '0'
+    bw2: '0'
+    bw20: '0'
+    bw21: '0'
+    bw22: '0'
+    bw23: '0'
+    bw24: '0'
+    bw25: '0'
+    bw26: '0'
+    bw27: '0'
+    bw28: '0'
+    bw29: '0'
+    bw3: '0'
+    bw30: '0'
+    bw31: '0'
+    bw4: '0'
+    bw5: '0'
+    bw6: '0'
+    bw7: '0'
+    bw8: '0'
+    bw9: '0'
+    clock_source0: ''
+    clock_source1: ''
+    clock_source2: ''
+    clock_source3: ''
+    clock_source4: ''
+    clock_source5: ''
+    clock_source6: ''
+    clock_source7: ''
+    comment: ''
+    corr0: '0.8'
+    corr1: '0'
+    corr10: '0'
+    corr11: '0'
+    corr12: '0'
+    corr13: '0'
+    corr14: '0'
+    corr15: '0'
+    corr16: '0'
+    corr17: '0'
+    corr18: '0'
+    corr19: '0'
+    corr2: '0'
+    corr20: '0'
+    corr21: '0'
+    corr22: '0'
+    corr23: '0'
+    corr24: '0'
+    corr25: '0'
+    corr26: '0'
+    corr27: '0'
+    corr28: '0'
+    corr29: '0'
+    corr3: '0'
+    corr30: '0'
+    corr31: '0'
+    corr4: '0'
+    corr5: '0'
+    corr6: '0'
+    corr7: '0'
+    corr8: '0'
+    corr9: '0'
+    freq0: center_freq
+    freq1: 100e6
+    freq10: 100e6
+    freq11: 100e6
+    freq12: 100e6
+    freq13: 100e6
+    freq14: 100e6
+    freq15: 100e6
+    freq16: 100e6
+    freq17: 100e6
+    freq18: 100e6
+    freq19: 100e6
+    freq2: 100e6
+    freq20: 100e6
+    freq21: 100e6
+    freq22: 100e6
+    freq23: 100e6
+    freq24: 100e6
+    freq25: 100e6
+    freq26: 100e6
+    freq27: 100e6
+    freq28: 100e6
+    freq29: 100e6
+    freq3: 100e6
+    freq30: 100e6
+    freq31: 100e6
+    freq4: 100e6
+    freq5: 100e6
+    freq6: 100e6
+    freq7: 100e6
+    freq8: 100e6
+    freq9: 100e6
+    gain0: '40'
+    gain1: '10'
+    gain10: '10'
+    gain11: '10'
+    gain12: '10'
+    gain13: '10'
+    gain14: '10'
+    gain15: '10'
+    gain16: '10'
+    gain17: '10'
+    gain18: '10'
+    gain19: '10'
+    gain2: '10'
+    gain20: '10'
+    gain21: '10'
+    gain22: '10'
+    gain23: '10'
+    gain24: '10'
+    gain25: '10'
+    gain26: '10'
+    gain27: '10'
+    gain28: '10'
+    gain29: '10'
+    gain3: '10'
+    gain30: '10'
+    gain31: '10'
+    gain4: '10'
+    gain5: '10'
+    gain6: '10'
+    gain7: '10'
+    gain8: '10'
+    gain9: '10'
+    if_gain0: '20'
+    if_gain1: '20'
+    if_gain10: '20'
+    if_gain11: '20'
+    if_gain12: '20'
+    if_gain13: '20'
+    if_gain14: '20'
+    if_gain15: '20'
+    if_gain16: '20'
+    if_gain17: '20'
+    if_gain18: '20'
+    if_gain19: '20'
+    if_gain2: '20'
+    if_gain20: '20'
+    if_gain21: '20'
+    if_gain22: '20'
+    if_gain23: '20'
+    if_gain24: '20'
+    if_gain25: '20'
+    if_gain26: '20'
+    if_gain27: '20'
+    if_gain28: '20'
+    if_gain29: '20'
+    if_gain3: '20'
+    if_gain30: '20'
+    if_gain31: '20'
+    if_gain4: '20'
+    if_gain5: '20'
+    if_gain6: '20'
+    if_gain7: '20'
+    if_gain8: '20'
+    if_gain9: '20'
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    nchan: '1'
+    num_mboards: '1'
+    sample_rate: hw_rate
+    sync: sync
+    time_source0: ''
+    time_source1: ''
+    time_source2: ''
+    time_source3: ''
+    time_source4: ''
+    time_source5: ''
+    time_source6: ''
+    time_source7: ''
+    type: fc32
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [928, 460.0]
+    rotation: 0
+    state: true
+- name: rational_resampler_xxx_0
+  id: rational_resampler_xxx
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    decim: int(samp_rate // math.gcd(int(hw_rate), int(samp_rate)))
+    fbw: '0'
+    interp: int(hw_rate // math.gcd(int(hw_rate), int(samp_rate)))
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    taps: '[]'
+    type: ccc
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [1152, 252.0]
+    rotation: 0
+    state: enabled
+
+connections:
+- [analog_frequency_modulator_fc_0, '0', blocks_throttle_0, '0']
+- [blocks_add_const_vxx_0, '0', analog_frequency_modulator_fc_0, '0']
+- [blocks_file_source_0, '0', blocks_unpack_k_bits_bb_0, '0']
+- [blocks_repeat_0, '0', blocks_uchar_to_float_0, '0']
+- [blocks_throttle_0, '0', rational_resampler_xxx_0, '0']
+- [blocks_uchar_to_float_0, '0', blocks_add_const_vxx_0, '0']
+- [blocks_unpack_k_bits_bb_0, '0', blocks_repeat_0, '0']
+- [rational_resampler_xxx_0, '0', osmosdr_sink_0, '0']
+
+metadata:
+  file_format: 1
+  grc_version: 3.10.5.1