@kaihengfeng: I found the problem was only really noticeable with earbuds. Headphones tended to hide the problem.
Although it's also worth noting the workaround 'amixer -c 0 set 'Headphone Mic Boost',0 1' sounds like it's working because it actually reduces the audio output volume/gain. With the workaround enabled, ALL audio is quieter so (like using big headphones) the problem could become unnoticeable just because of that. So saying the problem and the solution are directly related to 'Headphone Mic Boost' might be a red herring. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to pulseaudio in Ubuntu. https://bugs.launchpad.net/bugs/1654448 Title: XPS 13 9360 and 9350, Realtek ALC3246, Headphone audio hiss Status in Dell Sputnik: New Status in alsa-driver package in Ubuntu: Confirmed Status in linux package in Ubuntu: Confirmed Status in pulseaudio package in Ubuntu: Confirmed Bug description: Pertaining to 16.04 on a dell XPS 13 9360 ii alsa-base 1.0.25+dfsg-0ubuntu5 Advanced Linux Sound Architecture Driver Version k4.4.0-57-generic. When headphones are plugged in, there is a clearly audible hiss (white noise). This is present as soon as the headphones are plugged in, whether 'headphones' or 'headset' are selected from the pop-up box. Using alsamixer to debug the issue reveals that it is related to "Headphone Mic Boost" - the default setting is: dB gain 0.00, 0.00. If this is changed to: 10.00, 10.00 (one notch up) the hiss disappears. 20.00, 20.00 cause a louder hiss and 30.00, 30.00 causes an even louder hiss with high frequency audio artifacts. When the headphones are removed and plugged back in the Headphone Mic Boost setting returns to dB gain 0 and the problem also returns. This (problem and workaround) has been reported in the wild: https://news.ycombinator.com/item?id=13050843 and https://www.reddit.com/r/Dell/comments/4j1zz4/headphones_have_static_noise_with_ubuntu_1604_on/ for example To manage notifications about this bug go to: https://bugs.launchpad.net/dell-sputnik/+bug/1654448/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp