Ok, first delete the file /etc/modprobe.d/alsa-base.conf
Raspbian Jessie does not use this config file like Wheezy did.
Now, to set the USB sound card to your default card you will need to edit the file /usr/share/alsa/alsa.conf
with the command sudo nano /usr/share/alsa/alsa.conf
scroll down until you find the lines
defaults.ctl.card 0
defaults.pcm.card 0
and change them to
defaults.ctl.card 1
defaults.pcm.card 1
Explanation: USB sound cards are registered as card 1 on Raspbian Jessie. On Wheezy they would be registered as card -2 by default and editing /etc/modprobe.d/alsa-base.conf
would change that.
I do not know if this next step is necessary but without it my card wouldn't work.
Create and edit the file ~/.asoundrc
by using the command sudo nano
~/.asoundrc` and change it so that it only reads this:
pcm.!default {
type hw
card 1
}
ctl.!default {
type hw
card 1
}
Now your default audio out (speakers) and audio in (mic) are your usb device.