I managed to save an incomplete vmcore (I don't have enough free space on /), and I have some more information:
[ 1370.452329] usb 2-1.2: USB disconnect, device number 4
[ 1370.458255] BUG: unable to handle kernel NULL pointer dereference at 00000000000000c0
[ 1370.460213] IP: [<ffffffffa0739aae>] snd_complete_urb+0x22/0x9a [snd_usb_audio]
[ 1370.463136] PGD 0
[ 1370.465996] Oops: 0000 [#1] SMP
[ 1370.468878] CPU 1