Stream the sound of a sph0645 I2S mic in fm station on a Raspberry pi with the PiFmRds lib

I'm trying to stream the sound from a raspberry pi of a sph0645mic in fm with the PiFmRds librairy

Here's what I've tried:

after the install of the mic here's what I have:

$ arecord -l
**** List of CAPTURE Hardware Devices ****
card 1: sndrpii2scard [snd_rpi_i2s_card], device 0: simple-card_codec_link snd-soc-dummy-dai-0 [simple-card_codec_link snd-soc-dummy-dai-0]

then I can record normally without any problems with this command :

$ arecord -D plughw:0 -c1 -r 48000 -f S32_LE -t wav -V mono -v file.wav

I can stream the file :

$ sox -t mp3 /home/thib/file.wav -t wav - | sudo /home/thib/PiFmRds/src/pi_fm_rds -audio -

but here is my problem : I would like stream the direct output of my mic. For that I've tried :

$ sudo arecord -D plughw:1 -c1 -r 48000 -f S32_LE -t wav  | sudo ./pi_fm_rds -audio -

after that I've tried to use the loopback fuction but I don't have any sound in my receptor.

$sudo modprobe snd-aloop
 arecord -l
**** List of CAPTURE Hardware Devices ****
card 1: sndrpii2scard [snd_rpi_i2s_card], device 0: simple-card_codec_link snd-soc-dummy-dai-0 [simple-card_codec_link snd-soc-dummy-dai-0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 3: Loopback [Loopback], device 0: Loopback PCM [Loopback PCM]
  Subdevices: 8/8
  Subdevice #0: subdevice #0
  Subdevice #1: subdevice #1
  Subdevice #2: subdevice #2
  Subdevice #3: subdevice #3
  Subdevice #4: subdevice #4
  Subdevice #5: subdevice #5
  Subdevice #6: subdevice #6
  Subdevice #7: subdevice #7
card 3: Loopback [Loopback], device 1: Loopback PCM [Loopback PCM]
  Subdevices: 8/8
  Subdevice #0: subdevice #0
  Subdevice #1: subdevice #1
  Subdevice #2: subdevice #2
  Subdevice #3: subdevice #3
  Subdevice #4: subdevice #4
  Subdevice #5: subdevice #5
  Subdevice #6: subdevice #6
  Subdevice #7: subdevice #7
  
$ sudo arecord -D plughw:3 -c1 -r 48000 -f S32_LE -t wav  | sudo /home/thib/PiFmRds/src/pi_fm_rds

I've also tried to use a program like pure data but nothing change... Do you have any ideas ?