Switch default sound card, while both use the same driver

Question

I have problems with sound on my Linux Mint 17.1. It generally works, but gets interrupted by scratchy noise most of the time.

I followed some tutorials and here is what I found out:

$ LC_ALL=C sudo aplay -l
**** List of PLAYBACK Hardware Devices ****
No protocol specified
xcb_connection_has_error() returned true
Home directory not accessible: Permission denied
card 0: HDMI [HDA Intel HDMI], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA Intel HDMI], device 7: HDMI 1 [HDMI 1]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA Intel HDMI], device 8: HDMI 2 [HDMI 2]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: Intel [HDA Intel], device 0: ALC887-VD Analog [ALC887-VD Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: Intel [HDA Intel], device 1: ALC887-VD Digital [ALC887-VD Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0


$ lspci -v  # relevant parts
00:03.0 Audio device: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor HD Audio Controller (rev 06)
    Subsystem: Intel Corporation Device 2010
    Flags: bus master, fast devsel, latency 0, IRQ 50
    Memory at f7d14000 (64-bit, non-prefetchable) [size=16K]
    Capabilities: [50] Power Management version 2
    Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit-
    Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00
    Kernel driver in use: snd_hda_intel
--
00:1b.0 Audio device: Intel Corporation Device 8ca0
    Subsystem: Gigabyte Technology Co., Ltd Device a182
    Flags: bus master, fast devsel, latency 0, IRQ 51
    Memory at f7d10000 (64-bit, non-prefetchable) [size=16K]
    Capabilities: [50] Power Management version 2
    Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit+
    Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00
    Capabilities: [100] Virtual Channel
    Kernel driver in use: snd_hda_intel

00:1c.0 PCI bridge: Intel Corporation Device 8c90 (rev d0) (prog-if 00 [Normal decode])


$ cat /proc/asound/modules
 0 snd_hda_intel
 1 snd_hda_intel

It seems that I have two sound cards. I guess I should use the other one. One of the tutorials instructed me to set the order by adding lines like options snd_hda_intel index=0 to /etc/modprode.d/alsa-base, but in my case both cards use snd_hda_intel so it is pointless.

So how do I switch to the other sound card?

If I'm approching it the wrong way and you know how to solve it another way, any advice is welcome.

EDIT

I solved the problem using a link provided by @jcoppens. I did not have to switch sound cards, but:

• echo "options snd-hda-intel vid=8086 pid=8ca0 snoop=0" >> /etc/modprobe.d/sound.conf
• add intel_iommu=igfx_off to kernel command line

The problem is specific for intel cards.

Answer 1

Well, I don't own those cards and my distro is different, but I have a few suggestions:

Did you try adding options snd_hda_intel index=1? It seems you are using the index=0 card, so with the index=1 option you should be enabling the motherboard audio (and probably have to switch the connectors at the back).

Another way would be editing the alsa.conf file. The location might be different for you distro, in may case it's in /usr/share/alsa. There are lines which indicate the default card:

defaults.ctl.card 0   <-
defaults.pcm.card 0   <-
defaults.pcm.device 0    <-
defaults.pcm.subdevice -1
defaults.pcm.nonblock 1
defaults.pcm.compat 0    <-
defaults.pcm.minperiodtime 5000         # in us

I suggest modifying the ones marked witn <- to 1, and reboot to check.