Lu cat !

1. sudo nano /etc/asound.conf

2. Now put the following in it:

pcm.!default {
 type hw
 card 1
} 
ctl.!default {
 type hw
 card 1
} 

pcm.!default
You are setting up a default ALSA device. You can define as many devices
as you like for different cards (if you have more than one) and for
different purposed. Howver, there can only be one default device.

type hw
You are telling ALSA to output directly to hardware. Instead of going
through an ALSA plugin for extra processing such as…