Getting noise from DA7212

你好,

We are working on ERAGON410 board based product and linux Linaro-18 platfrom. We are using DA7212 in slave mode and set MCLK to 9.6 MHz.

#1If we apply below commands which will play directly from AUX, We can hear the noise in the HP if the volume level is more then 55-60%. Here we are not playing anything at AUX side.

amixer -q cset name='Aux Switch' on
amixer -q cset name='Mixin Left Aux Left Switch' on
amixer -q cset name='Mixin Right Aux Right Switch' on
amixer -q cset name='ADC Switch' on
amixer -q cset name='Mixout Right Mixin Right Switch' on
amixer -q cset name='Mixout Left Mixin Left Switch' on
amixer -q cset name='Headphone Volume' 70%
amixer -q cset name='Headphone Switch' on
amixer -q cset name='Mixout Left DAC Left Switch' on
amixer -q cset name='Mixout Right DAC Right Switch' on

#2If we play from the DAI after applying below configurations, we do not hear the noise in the HP,

amixer -q cset name='Aux Switch' on
amixer -q cset name='Mixin Left Aux Left Switch' on
amixer -q cset name='Mixin Right Aux Right Switch' on
amixer -q cset name='ADC Switch' on
amixer -q cset name='Mixout Right Mixin Right Switch' off
amixer -q cset name='Mixout Left Mixin Left Switch' off
amixer -q cset name='Headphone Volume' 71%
amixer -q cset name='Headphone Switch' on
amixer -q cset name='Mixout Left DAC Left Switch' on
amixer -q cset name='Mixout Right DAC Right Switch' on
amixer -q cset name='DAC Left Source MUX' 'DAI Input Left'
amixer -q cset name='DAC Right Source MUX' 'DAI Input Right'

Now, here if we add below configurations which connect AUX output to Mixout Left/Right, then we can hear the noise as per scenario #1.

amixer -q cset name='Mixout Right Mixin Right Switch' on
amixer -q cset name='Mixout Left Mixin Left Switch' on

Therefore, it seems like the issue we are getting is from the AUX side.

Can you please help here further?

Regards.