I had noticed the loud pop even with headphones attached to the headphone jack on the Audio Mezzanine board. I haven’t had a chance to go back and retest this with the Android build on the board, but I don’t remember this being a problem under Android.
I suspect that the Android builds do something different when powering up the headphone jack to avoid the pop noise. Maybe @srini or @nico in the Linaro team can take a look at this.
In the mean time, can you file a bug report on this at bugs.96boards.org so that the problem can be tracked through to a conclusion. Thanks.
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