I have a linux ubuntu 12.04 server machine which works with an usb sound card.When rebooting the machine, sometimes the usb sound card is recognized and sometimes not, I cannot figure out a reason for this.I understand when the sound card is recognized because when I issue the command:cat /proc/asound/modulesI can see listed or not the line snd_usb_audio.Analyzing the /var/log/kernel.log I can see sometimes (when it works)kernel: [    6.236564] usbcore: registered new interface driver snd-usb-audioand other times (when it is not recognized and listed):kernel: [    7.126855] snd-usb-audio: probe of 2-1.2:1.0 failed with error -5kernel: [    7.126876] usbcore: registered new interface driver snd-usb-audioDoes anybody know how to ensure that the usb sound card is always recognized?
ubuntu usb sound card sometimes recognized and sometimes not at boot
ubuntu;drivers;audio;usb
Ok this solved the problem:1) blacklist the integrated audio cardsudo nano /etc/modprobe.d/blacklist.confand add the lineblacklist snd_hdma_intelwhere the name snd_hdma_intel is retrieved after issuing the commandcat /proc/asound/modules(for example the output for me was)0 snd_hdma_intel1 snd_usb_audio2) edit the following file:sudo nano /etc/modprobe.d/alsa-base.confcomment the lines regarding snd-usb-audio this way:#options snd-usb-audio index=-23) just reboot