To reproduce I go to:
Settings > Sound
or any program that makes use of the sound device. I guess the device then gets enabled/awakened and starts sending the noise to the headphones. Once I close the window the noise stops after a moment. It is quite loud and cannot really be masked by any actual audio being played. It is the same with all the headphones I tried.
Below is a link to a recording that I've done with a mobile phone. The recording is a bit bassy and with background hiss whereas what goes through the headphones has no hiss and is very crisp, with this uniform popping sound peppered with crackling noises, both can be heard in the recording.
Here is a snippet of lspci -v
:
00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
Subsystem: Fujitsu Limited. Sunrise Point-LP HD Audio
Flags: bus master, fast devsel, latency 32, IRQ 143
Memory at c1340000 (64-bit, non-prefetchable) [size=16K]
Memory at c1320000 (64-bit, non-prefetchable) [size=64K]
Capabilities: <access denied>
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel
The solution suggested here only makes the noise stay on forever in my case.