I am not sure this is an alsa-specific bug. Looks to be more of an issue with the Nvidia card and the way it handles HDMI audio. This also affects a BTO 15CL76 notebook (I7-6700HQ / GTX1060) set in DISCRETE mode. No HDMI audio device shows up at all. The active nvidia driver (as of writing) is nvidia_367. No bbswitch/bumblebee installed as Hybrid mode is disabled.
Suggestions on the nvidia forum are to shutdown your X environment and then run the following commands as root: https://devtalk.nvidia.com/default/topic/609790/linux/no-hdmi-sound-w -optimus-in-linux/ rmmod nvidia echo 1 > /sys/bus/pci/devices/0000\:00\:01.0/remove echo 1 > /sys/bus/pci/rescan This also had no effects - the Nvidia device comes back online but without the audio device showing up. Here's the output of lspci -H 1: fludizz@tongerlo:~$ sudo lspci -H 1 00:00.0 Host bridge: Intel Corporation Sky Lake Host Bridge/DRAM Registers (rev 07) 00:01.0 PCI bridge: Intel Corporation Sky Lake PCIe Controller (x16) (rev 07) 00:14.0 USB controller: Intel Corporation Sunrise Point-H USB 3.0 xHCI Controller (rev 31) 00:16.0 Communication controller: Intel Corporation Sunrise Point-H CSME HECI #1 (rev 31) 00:17.0 SATA controller: Intel Corporation Sunrise Point-H SATA Controller [AHCI mode] (rev 31) 00:1c.0 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root Port #1 (rev f1) 00:1c.4 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root Port #5 (rev f1) 00:1c.6 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root Port #7 (rev f1) 00:1d.0 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root Port #9 (rev f1) 00:1f.0 ISA bridge: Intel Corporation Sunrise Point-H LPC Controller (rev 31) 00:1f.2 Memory controller: Intel Corporation Sunrise Point-H PMC (rev 31) 00:1f.3 Audio device: Intel Corporation Sunrise Point-H HD Audio (rev 31) 00:1f.4 SMBus: Intel Corporation Sunrise Point-H SMBus (rev 31) 01:00.0 VGA compatible controller: NVIDIA Corporation Device 1c60 (rev a1) 6d:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. Device 5287 (rev 01) 6d:00.1 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 12) 6e:00.0 Network controller: Intel Corporation Wireless 8260 (rev 3a) 6f:00.0 Non-Volatile memory controller: Intel Corporation Device f1a5 (rev 03) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1377653 Title: HDMI sound output not detected / NVIDIA optimus laptop To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1377653/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
