modena@makoto 23:12:41/141024(~)% \
env AUDIODEV=/dev/audio1 play /export/blackphone_an.mp3 

 File Size: 234k      Bit Rate: 129k
  Encoding: MPEG audio    
  Channels: 2 @ 16-bit   
Samplerate: 44100Hz      
Replaygain: off         
  Duration: 00:00:14.50  

Audio -> Wave File Source
Audio -> Audio Sink

の二つを選んで、つなぎ、Sample Rate は 44.1kHz にしておく
まず *.mp3 だと、wav file ではない、と言って相手にしてくれない

ちなみに、今回は root 権限でなくても大丈夫
そこで別の *.wav を選んでつないで見るが、

INFO: Audio sink arch: portaudio

Using Default Device
/dev/audio is the chosen device using OSS as the host
Latency =  0.02133, requested sampling_rate = 44100
d_portaudio_buffer_size_frames = 941
/home/makoto/.gnuradio/prefs/vmcircbuf_default_factory: No such file or directory
vmcircbuf_createfilemapping: createfilemapping is not available
gr::vmcircbuf_sysv_shm: shmat(1): Too many open files
gr::vmcircbuf_sysv_shm: shmat(1): Too many open files
gr::vmcircbuf_sysv_shm: shmat(1): Too many open files
gr::vmcircbuf_sysv_shm: shmat(1): Too many open files
gr::vmcircbuf_sysv_shm: shmat(1): Too many open files
gr::vmcircbuf_sysv_shm: shmat(1): Too many open files
gr::vmcircbuf_mmap_shm_open: mmap or shm_open is not available

となってしまう。やはり root にして、device を /dev/audio1 にしたら音が出た。
しかし、しばらくすると、例によって途切れる。

Generating: "/amd/u/u/home/makoto/top_block.py"

Executing: "/amd/u/u/home/makoto/top_block.py"

INFO: Audio sink arch: portaudio

Test Devices
Testing device name: /dev/audio
Testing device name: /dev/audio1  Chosen!
/dev/audio1 using OSS as the host
Latency =  0.02133, requested sampling_rate = 44100
d_portaudio_buffer_size_frames = 941
aUaUaUaUaUaUaUaUaUaUaUaUaUaU

aUaUaUaUaUaUaUaUaUaUaUaUaUaU
という文字は何だろう。これが途切れる原因の気がする。

The aU is
because your audio subsystem is experiencing underruns, probably because
you have a sample-rate issue in your flow-graph.

Underrun とは、供給が足りない、遅い、という意味かな。 別の機械に USB audio をつないだが、

:00 z87 /netbsd: uaudio0 at uhub2 port 4 configuration 1 interface 0
:00 z87 /netbsd: uaudio0: Burr-Brown from TI USB Audio CODEC, rev 1.10/1.00, addr 4
:00 z87 /netbsd: uaudio0: audio rev 1.00
:00 z87 /netbsd: audio2 at uaudio0: full duplex, playback, capture, independent
:00 z87 /netbsd: uhidev0 at uhub2 port 4 configuration 1 interface 3
:00 z87 /netbsd: uhidev0: Burr-Brown from TI USB Audio CODEC, rev 1.10/1.00, addr 4, iclass 3/0
:00 z87 /netbsd: uhid0 at uhidev0: input=1, output=0, feature=0
:24 z87 /netbsd: ehci1: error opening low/full speed isoc endpoint.
:24 z87 /netbsd: ehci1: a low/full speed device is attached to a USB2 hub, 
		 and transaction translations are not yet supported.
:24 z87 /netbsd: ehci1: reattach the device to the root hub instead.

借り物の Core i7 3.4GHz Quad Core に 6.1_STABLE が入れてある方だと、 aUaUaUaUaUaU は出るものの *.wav の再生は内蔵の sound chip を使って気持良く聞ける。
それも、root でなくて良い。 rtl-sdr の方は、一応つながって実行は出来たが、 まだ FM (80.7MHz) の受信は出来ていない。