ReSpeaker 4mic array v2.0 merged playback channel empty

Hello,



I am trying to use the 4mic array v2.0 with a raspberry pi 3b+.

The mic has been factory reset using : python dfu.py --revertfactory.



Our raspberry is connected to the mic through usb and use it as default output. Our speaker is then connected through jack to the mic.

The speaker is playing sound (so the mic receives sound) but the merged playback channel is always empty.



Pactl info :
</s><i> </i>Server String: /run/user/1000/pulse/native Library Protocol Version: 32 Server Protocol Version: 32 Is Local: yes Client Index: 53 Tile Size: 65496 User Name: pi Host Name: raspberrypi Server Name: pulseaudio Server Version: 10.0 Default Sample Specification: s16le 2ch 44100Hz Default Channel Map: front-left,front-right Default Sink: alsa_output.usb-SEEED_ReSpeaker_4_Mic_Array__UAC1.0_-00.iec958-stereo Default Source: alsa_input.usb-SEEED_ReSpeaker_4_Mic_Array__UAC1.0_-00.multichannel-input Cookie: b4b6:48a3 <e>

We tested the same microphone on a computer with the same pactl info output and it works.

Do you have any idea why it does not on the raspberry pi ?



Thanks in advance,

Hi There

maybe you should use alsa to concrol mic array . it is very convenient for devlopmenter to record merged playback channel



from the iamge ,The arrow points to merged playback channel

Hello,



Thanks for the response. I finally understood what was going wrong in my case: the merged playback channel was not empty but lower as other channels. The signal was amplified but after the mic treatments, that is why the DSP function was not working as well as I need it to !



Anyway, it is now working ! Thanks for your advice.