Comment 22 for bug 1332900

https://bugs.launchpad.net/ubuntu/+source/alsa-lib/+bug/1286021

do you get sound from from subwoofer after retasking node 0x1a ?

since you have two headphone , speakers and subwoofer

the current driver only create two volume controls for headphone And speaker

you may need to retask one headphone Jack to UN connected if you want the driver to create volume controls for speaker and subwoofer

https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/Documentation/sound/alsa/HD-Audio.txt

`CONFIG_SND_HDA_HWDEP` is a useful option for debugging the driver.
When this is enabled, the driver creates hardware-dependent devices
(one per each codec), and you have a raw access to the device via
these device files. For example, `hwC0D2` will be created for the
codec slot #2 of the first card (#0). For debug-tools such as
hda-verb and hda-analyzer, the hwdep device has to be enabled.
Thus, it'd be better to turn this on always.

`CONFIG_SND_HDA_RECONFIG` is a new option, and this depends on the
hwdep option above. When enabled, you'll have some sysfs files under
the corresponding hwdep directory. See "HD-audio reconfiguration"
section below.

http://git.alsa-project.org/?p=alsa-tools.git;a=blob;f=hdajackretask/README;hb=HEAD

apply now button work only when driver is build with reconfig and the program can kill pulseaudio and can dynamic receive configure the driver

the alternative is to use hda analyzer , just set pinctl of the subwoofer node to out and connected the node to one of the audio output , unmute the switch along the path and change the volume slider