I upgraded to Ubuntu 18.04 and sound disappeared and showed the infamous "Dummy Output", I thought the problem was with alsa and pulseaudio so I removed them and reinstalled them but that did not fix it.
I tried the command aplay -l
The output was : aplay: device_list:270: no soundcards found..
I tried lspci
and the output was:
00:00.0 Host bridge: Intel Corporation Skylake Host Bridge/DRAM Registers (rev 08)
00:02.0 VGA compatible controller: Intel Corporation HD Graphics 520 (rev 07)
00:14.0 USB controller: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller (rev 21)
00:14.2 Signal processing controller: Intel Corporation Sunrise Point-LP Thermal subsystem (rev 21)
00:15.0 Signal processing controller: Intel Corporation Sunrise Point-LP Serial IO I2C Controller #0 (rev 21)
00:15.1 Signal processing controller: Intel Corporation Sunrise Point-LP Serial IO I2C Controller #1 (rev 21)
00:16.0 Communication controller: Intel Corporation Sunrise Point-LP CSME HECI #1 (rev 21)
00:17.0 SATA controller: Intel Corporation Sunrise Point-LP SATA Controller [AHCI mode] (rev 21)
00:1c.0 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #5 (rev f1)
00:1c.5 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #6 (rev f1)
00:1f.0 ISA bridge: Intel Corporation Sunrise Point-LP LPC Controller (rev 21)
00:1f.2 Memory controller: Intel Corporation Sunrise Point-LP PMC (rev 21)
00:1f.4 SMBus: Intel Corporation Sunrise Point-LP SMBus (rev 21)
01:00.0 Network controller: Intel Corporation Wireless 3160 (rev 83)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller (rev 07)
As you can see without Audio device.
I ran the alsa-info script https://gist.github.com/craftyjon/902247
and This was the output:
upload=true&script=true&cardinfo=
!!################################
!!ALSA Information Script v 0.4.64
!!################################
> !!Script ran on: Sat May 5 14:11:34 UTC 2018
> !!Linux Distribution
!!------------------
> Ubuntu 18.04 LTS \n \l DISTRIB_ID=Ubuntu DISTRIB_DESCRIPTION="Ubuntu 18.04 LTS" NAME="Ubuntu" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 18.04 LTS" HOME_URL="https://www.ubuntu.com/" SUPPORT_URL="https://help.ubuntu.com/" BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/" PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy" UBUNTU_CODENAME=bionic
> !!DMI Information
!!---------------
> Manufacturer: Dell Inc.
Product Name: Inspiron 5559
Product Version:
Firmware Version: 1.1.6
Board Vendor: Dell Inc.
Board Name: 04D1V1
> !!ACPI Device Status Information
!!---------------
> /sys/bus/acpi/devices/ACPI0003:00/status 15
/sys/bus/acpi/devices/ACPI000C:00/status 15
/sys/bus/acpi/devices/DELLABCE:00/status 15
/sys/bus/acpi/devices/DLLC6B2:00/status 15
/sys/bus/acpi/devices/DLLK06B2:00/status 15
/sys/bus/acpi/devices/INT33A1:00/status 15
/sys/bus/acpi/devices/INT33D0:00/status 15
/sys/bus/acpi/devices/INT340E:00/status 15
/sys/bus/acpi/devices/INT344B:00/status 15
/sys/bus/acpi/devices/INT3F0D:00/status 15
/sys/bus/acpi/devices/LNXPOWER:00/status 1
/sys/bus/acpi/devices/LNXPOWER:01/status 1
/sys/bus/acpi/devices/LNXPOWER:02/status 1
/sys/bus/acpi/devices/PNP0103:00/status 15
/sys/bus/acpi/devices/PNP0C02:03/status 3
/sys/bus/acpi/devices/PNP0C02:04/status 3
/sys/bus/acpi/devices/PNP0C09:00/status 15
/sys/bus/acpi/devices/PNP0C0A:00/status 31
/sys/bus/acpi/devices/PNP0C0F:00/status 9
/sys/bus/acpi/devices/PNP0C0F:01/status 9
/sys/bus/acpi/devices/PNP0C0F:02/status 9
/sys/bus/acpi/devices/PNP0C0F:03/status 9
/sys/bus/acpi/devices/PNP0C0F:04/status 9
/sys/bus/acpi/devices/PNP0C0F:05/status 9
/sys/bus/acpi/devices/PNP0C0F:06/status 9
/sys/bus/acpi/devices/PNP0C0F:07/status 9
/sys/bus/acpi/devices/device:4e/status 15
/sys/bus/acpi/devices/device:4f/status 15
/sys/bus/acpi/devices/device:53/status 15
/sys/bus/acpi/devices/device:66/status 11
> !!Kernel Information
!!------------------
> Kernel release: 4.15.0-20-generic
Operating System: GNU/Linux
Architecture: x86_64
Processor: x86_64
SMP Enabled: Yes
> !!ALSA Version
!!------------
> Driver version:
Library version: 1.1.3
Utilities version: 1.1.3
> !!Loaded ALSA modules
!!-------------------
> !!Sound Servers on this system
!!----------------------------
> Pulseaudio:
Installed - Yes (/usr/bin/pulseaudio)
Running - Yes
> !!Soundcards recognised by ALSA
!!-----------------------------
> !!PCI Soundcards installed in the system
!!--------------------------------------
> !!Advanced information - PCI Vendor/Device/Subsystem ID's
!!-------------------------------------------------------
> !!Modprobe options (Sound related)
!!--------------------------------
> snd_pcsp: index=-2
> snd_usb_audio: index=-2
> snd_atiixp_modem: index=-2
> snd_intel8x0m: index=-2
> snd_via82xx_modem: index=-2
> snd_atiixp_modem: index=-2
> snd_intel8x0m: index=-2
> snd_via82xx_modem: index=-2
> snd_usb_audio: index=-2
> snd_usb_caiaq: index=-2
> snd_usb_ua101: index=-2
> snd_usb_us122l: index=-2
> snd_usb_usx2y: index=-2
> snd_cmipci: mpu_port=0x330 fm_port=0x388
> snd_pcsp: index=-2
> snd_usb_audio: index=-2
> snd_hda_intel: jackpoll_ms=500
> !!Loaded sound module options
!!---------------------------
> !!ALSA Device nodes
!!-----------------
> crw-rw----+ 1 root audio 116, 1 May 5 15:58 /dev/snd/seq
> crw-rw----+ 1 root audio 116, 33 May 5 15:58 /dev/snd/timer
> !!Aplay/Arecord output
!!--------------------
> APLAY
> aplay: device_list:270: no soundcards found...
> ARECORD
> arecord: device_list:270: no soundcards found...
> !!Amixer output
!!-------------
> !!Alsactl output
!!--------------
> --startcollapse--
> --endcollapse--
> !!All Loaded Modules
!!------------------
> Module
ccm
vmw_vsock_vmci_transport
vsock
vmw_vmci
cmac
bnep
nls_iso8859_1
rtsx_usb_ms
memstick
uvcvideo
videobuf2_vmalloc
videobuf2_memops
videobuf2_v4l2
videobuf2_core
videodev
media
btusb
btrtl
btbcm
btintel
bluetooth
ecdh_generic
arc4
iwlmvm
mac80211
hid_multitouch
dell_laptop
dell_smbios_smm
dcdbas
dell_smm_hwmon
intel_rapl
x86_pkg_temp_thermal
intel_powerclamp
coretemp
kvm_intel
kvm
irqbypass
crct10dif_pclmul
crc32_pclmul
ghash_clmulni_intel
pcbc
aesni_intel
aes_x86_64
crypto_simd
glue_helper
cryptd
intel_cstate
iwlwifi
intel_rapl_perf
cfg80211
joydev
dell_wmi
input_leds
dell_smbios_wmi
dell_smbios
serio_raw
sparse_keymap
dell_wmi_descriptor
wmi_bmof
acpi_pad
idma64
virt_dma
shpchp
mei_me
intel_pch_thermal
mei
intel_lpss_pci
intel_lpss
dell_rbtn
mac_hid
sch_fq_codel
parport_pc
ppdev
lp
parport
ip_tables
x_tables
autofs4
rtsx_usb_sdmmc
rtsx_usb
i915
i2c_algo_bit
drm_kms_helper
syscopyarea
sysfillrect
sysimgblt
psmouse
fb_sys_fops
r8169
ahci
drm
mii
libahci
i2c_hid
wmi
hid
video
pinctrl_sunrisepoint
> !!ALSA/HDA dmesg
!!--------------
I have dealt with sounds problems many times before but at least each time the card was detected by lspci
command I don't know if that is a hardware problem.
UPDATE:
I restored the default BIOS settings and the soundcard is visible now. The problem now is that in pavucontrol, the option "Analog Stereo Duplex" and "Analog stereo Input/Output" for that matter are missing. I reinstalled pulseaudio and alsa but it did not work.
Best Answer
I had a similar problems with USB card (Asus Xonar U7) on Ubuntu 18.04
I solved it using instructions from this answer https://askubuntu.com/a/1104763/354702 by João Pimentel Ferreira
1) Remove the ALSA packages.
2) Reinstall the same packages.
3) Install further audio addon packages
4) Be sure to add the user to group audio
5) reboot