In order to re-enable internal sound card you must do:
1. edit sudo nano /etc/modprobe.d/raspi-blacklist.conf and comment (#) or remove blacklist snd_bcm2835
2. edit /boot/config.txt and (if exists) comment (#) or remove dtparam=audio=off and then add dtparam=audio=on line
Please note that microphone input is mandatory (even if you do not use it) and OpenAuto Pro may not work as expected without it.
1. edit sudo nano /etc/modprobe.d/raspi-blacklist.conf and comment (#) or remove blacklist snd_bcm2835
2. edit /boot/config.txt and (if exists) comment (#) or remove dtparam=audio=off and then add dtparam=audio=on line
Please note that microphone input is mandatory (even if you do not use it) and OpenAuto Pro may not work as expected without it.