^^^
Confirmed on an XPS 13 9350 too. And the 'Headphone Mic Boost' workaround works. Although like others, I find that concerning since it should in theory make the problem worse or make no difference.
Also confirmed the problem persists with:
* 3-contact earphones (Sony)
* 4-contact Apple Earpods
* 4-contact Bose AE2 headphones (Apple-compatible cable)
All of these experience the hiss, but the Bose almost none (much harder to notice). I think the most interesting test should be to try some proper Android/Samsung/Nokia wired headphones/earphones in future.
If it turns out there's nothing wrong with the physical connection then this sounds like a kernel problem still.
kaihengfeng: I have just tested your kernel on zesty and it made no difference. The problem remains and the same old amixer workaround is required.
^^^
Confirmed on an XPS 13 9350 too. And the 'Headphone Mic Boost' workaround works. Although like others, I find that concerning since it should in theory make the problem worse or make no difference.
Also confirmed the problem persists with:
* 3-contact earphones (Sony)
* 4-contact Apple Earpods
* 4-contact Bose AE2 headphones (Apple-compatible cable)
All of these experience the hiss, but the Bose almost none (much harder to notice). I think the most interesting test should be to try some proper Android/ Samsung/ Nokia wired headphones/ earphones in future.
If it turns out there's nothing wrong with the physical connection then this sounds like a kernel problem still.
kaihengfeng: I have just tested your kernel on zesty and it made no difference. The problem remains and the same old amixer workaround is required.