There is a strange noise from my headphones on Lenovo T440. The sound is like when you tune your radio, but you get a wrong frequency and you hear unpleasant noise. The noise starts when Ubuntu 14.04 boots up and ends after a shutdown. It is coming out only through my headphones, there is no noise through the speakers.
The strange thing is that the noise disappears when any sound is played or if I enter sound preferences. But when a sound is stopped, it appears again after 10 seconds or less. Also, the noise goes way down (or maybe even disappears) if I put in my laptop charger and stop the music.
No matter how I change my volume level, the noise level is the same. It seems like the output is not disabled after sound stops.
sudo aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: HDMI [HDA Intel HDMI], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: HDMI [HDA Intel HDMI], device 7: HDMI 1 [HDMI 1]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: HDMI [HDA Intel HDMI], device 8: HDMI 2 [HDMI 2]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: PCH [HDA Intel PCH], device 0: ALC292 Analog [ALC292 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
beep
channel inalsamixer
from0
to something else and back to0
– EECOLOR Nov 02 '15 at 01:01