Dear community:
platform:iMX6 DualLite + Linux BSP4.1.15
1. We can hear pop noise when playback beep audio. beep device configured as below in asound.conf
aplay -v -D beep beep1.wav
2. we found the audio lost 1~2 waveform in the beginning when capture the audio by hardware connecting to the amplifier as above configuration.
3. we could acquire complete waveform whe configure beep device as plughw like this.
4. add 20ms null data to the beginning of the beep file, then we could acquire complete waveform. but the waveform reversed . upper is original beep file, below is beep file adding 20ms null data
why dmix lost some audio? and the audio be reversed?
Thanks a lot for any tips .
Hi yang
one can try to decrease pop using volume control or codec stby signal as
described on
iMX6Q+SGTL5000 have pop noise in suspend/resume and shutdown processes
try with latest NXP Linux L4.14.98, link
https://source.codeaurora.org/external/imx/linux-imx/tree/?h=imx_4.14.98_2.0.0_ga
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------