ubuntu usb sound card sometimes recognized and sometimes not at boot

view full story

http://unix.stackexchange.com – 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/modules I 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-audio and other times (when it is not recognized and listed): kernel: [ 7.126855] snd (HowTos)