#The below 2 sections are commented, they control the default sound card to use #This set up is for a Pi with an I2S microphone attached using the guide #from adafruit at # https://learn.adafruit.com/adafruit-i2s-mems-microphone-breakout #Uncomment and the I2S will be your default card (assuming same setup) #but you won't get audio playback because both recording and playback will be #defaulted #TODO - Figure out how to set default for recording separately #To adjust use aplay -l to work out the devices you have and their card number #For recording devices use arecord -l #pcm.!default { # type hw # card 1 #} #ctl.!default { # type hw # card 1 #} #This section makes a reference to your I2S hardware, adjust the card name # to what is shown in arecord -l after card x: before the name in [] #You may have to adjust channel count also but stick with default first pcm.dmic_hw { type hw card sndrpii2scard channels 1 format S32_LE } #This is the software volume control, it links to the hardware above and after # saving the .asoundrc file you can type alsamixer, press F6 to select # your I2S mic then F4 to set the recording volume and arrow up and down # to adjust the volume # After adjusting the volume - go for 50 percent at first, you can do # something like # arecord -D dmic_sv -c2 -r 48000 -f S32_LE -t wav -V mono -v myfile.wav pcm.dmic_sv { type softvol slave.pcm dmic_hw control { name "Boost Capture Volume" card sndrpii2scard } min_dB -3.0 max_dB 30.0 }