Comment 5 for bug 381439

@Charly Mendez: If I remember correctly, I didn't find an "options" file either under /etc/modprobe.d; however, you can create it. When you restart alsa, you might receive a message that tells you that the file should be called options.conf. It's OK, you can do that.

However, it is my understanding that each time you modify these files (alsa-base.conf and options.conf) you need more that restarting alsa i.e. you need to reboot your PC.