I remember hearing the sound in Atlantis, and was checking all audio jack cables, but could not find unplugged one. And it was not that clear which DUT was doing it. Now this mistery is solved :)
sontis@ was able to reproduce this issue manually playing on headphones after reboot on daisy, but not very consistent. He pointed out we do have a test for this, which actually passes with the recorded file sounding OK on both channels(attaching the file):
https://screenshot.googleplex.com/BKCTuesPZpL

Deleted: recorded_filtered.raw.wav 3.6 MB

recorded_filtered.raw.wav 3.6 MB Download

Yes, the problem is the audio leak to speaker since speaker switch is not turned off.
Headphone have sound too.

Hi Sridhar, could you please check daisy_spring and daisy_skate too ?
Thanks!

Chromeos : 9460.50.0
Not able to reproduce this issue on daisy_spring and daisy_skate.

Thank you!

CL posted for daisy: https://chromium-review.googlesource.com/#/c/516325/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/adhd/+/09252a1bf9b2ee54cf6d9ebb48b2bffce8ad153e

commit 09252a1bf9b2ee54cf6d9ebb48b2bffce8ad153e
Author: Cheng-Yi Chiang <cychiang@chromium.org>
Date: Mon Jun 05 06:44:25 2017

daisy: Turn off speaker switch when headphone is enabled

Speaker should be switched off when headphone is enabled.
Otherwise, when CRAS starts with headphone plugged, and headphone is
enumerated as the first node, speaker switch will still remain on, and
cause sound to be played to speaker and headphone at the same time.

BUG= chromium:726175 
TEST=Boot with headphone plugged. Check audio does not play to speaker.

Change-Id: Ifcae91342ae1a227a36c61f285b8fee36ffc7e88
Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/516325
Reviewed-by: Hsinyu Chao <hychao@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>

[modify] https://crrev.com/09252a1bf9b2ee54cf6d9ebb48b2bffce8ad153e/ucm-config/daisy/DAISY-I2S/HiFi.conf

This bug requires manual review: We are only 0 days from stable.
Please contact the milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), gkihumba@(ChromeOS), Abdul Syed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Add merge request to 59 and 60.
The fix was in UCM config file which affects daisy only.
Thanks!

Please mark appropriate OS. 

Your change meets the bar and is auto-approved for M60. Please go ahead and merge the CL to branch 3112 manually. Please contact milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), josafat@(ChromeOS), bustamante@(Desktop)

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The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/adhd/+/f233e7fd1511b76d6f75e18f97e945c1e594bf6d

commit f233e7fd1511b76d6f75e18f97e945c1e594bf6d
Author: Cheng-Yi Chiang <cychiang@chromium.org>
Date: Tue Jun 06 08:24:37 2017

daisy: Turn off speaker switch when headphone is enabled

Speaker should be switched off when headphone is enabled.
Otherwise, when CRAS starts with headphone plugged, and headphone is
enumerated as the first node, speaker switch will still remain on, and
cause sound to be played to speaker and headphone at the same time.

BUG= chromium:726175 
TEST=Boot with headphone plugged. Check audio does not play to speaker.

Change-Id: Ifcae91342ae1a227a36c61f285b8fee36ffc7e88
Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Previous-Reviewed-on: https://chromium-review.googlesource.com/516325
(cherry picked from commit 9e0d741926b7b258a816587c4943fa800014b582)
Reviewed-on: https://chromium-review.googlesource.com/525156

[modify] https://crrev.com/f233e7fd1511b76d6f75e18f97e945c1e594bf6d/ucm-config/daisy/DAISY-I2S/HiFi.conf

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/adhd/+/cb47688dc36554f103fee6c4df4cad9c8f3a1c78

commit cb47688dc36554f103fee6c4df4cad9c8f3a1c78
Author: Cheng-Yi Chiang <cychiang@chromium.org>
Date: Thu Jun 08 06:50:44 2017

daisy: Turn off speaker switch when headphone is enabled

Speaker should be switched off when headphone is enabled.
Otherwise, when CRAS starts with headphone plugged, and headphone is
enumerated as the first node, speaker switch will still remain on, and
cause sound to be played to speaker and headphone at the same time.

BUG= chromium:726175 
TEST=Boot with headphone plugged. Check audio does not play to speaker.

Change-Id: Ifcae91342ae1a227a36c61f285b8fee36ffc7e88
Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Previous-Reviewed-on: https://chromium-review.googlesource.com/516325
(cherry picked from commit 1c3b224109822e976e43f5a77c8c129a99663240)
Reviewed-on: https://chromium-review.googlesource.com/527975

[modify] https://crrev.com/cb47688dc36554f103fee6c4df4cad9c8f3a1c78/ucm-config/daisy/DAISY-I2S/HiFi.conf

Fix merged to R59 and R60.
Thanks!

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

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Verified on M60 build 9592.22.0