Arch Linux

Description:

On a Lenovo P50, when using the audio output jack, if audio has not been present for ~10 seconds, a bassy "thump" is heard followed by a high-pitched whine. It seems like the audio device is going into some kind of sleep mode and playing erroneous sound. This seems to happen with the audio output jack only as the internal speakers don't have this issue.

Additional info:
* linux 4.15.13-1
* pulseaudio 11.1-1
* lspci for audio device: Audio device: Intel Corporation Sunrise Point-H HD Audio (rev 31)

output of $ lsmod | grep snd:
snd_hda_codec_realtek 110592 1
snd_hda_codec_generic 86016 1 snd_hda_codec_realtek
snd_hda_intel 45056 3
snd_hda_codec 151552 3 snd_hda_intel,snd_hda_codec_generic,snd_hda_codec_realtek
snd_hda_core 94208 4 snd_hda_intel,snd_hda_codec,snd_hda_codec_generic,snd_hda_codec_realtek
snd_hwdep 20480 1 snd_hda_codec
snd_pcm 135168 3 snd_hda_intel,snd_hda_codec,snd_hda_core
snd_timer 36864 1 snd_pcm
snd 98304 14 snd_hda_intel,snd_hwdep,snd_hda_codec,snd_timer,thinkpad_acpi,snd_hda_codec_generic,snd_hda_codec_realtek,snd_pcm
soundcore 16384 1 snd

Steps to reproduce:
1. Acquire a Lenovo P50 with Arch Linux synced to latest packages.
2. Install PulseAudio.
3. Plug in a device to the audio output jack (i.e. headphones).
4. Play a video on YouTube (this is what I'm doing exactly; you can probably test other sources).
5. Wait ~10 seconds.
6. Observe "thump" sound and high pitched whine.