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@@ -1,3 +1,4 @@
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+=====================
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Audio Pops and Clicks
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=====================
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@@ -20,10 +21,11 @@ currently, however future audio codec hardware will have better pop and click
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suppression. Pops can be reduced within playback by powering the audio
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components in a specific order. This order is different for startup and
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shutdown and follows some basic rules:-
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+::
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- Startup Order :- DAC --> Mixers --> Output PGA --> Digital Unmute
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-
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- Shutdown Order :- Digital Mute --> Output PGA --> Mixers --> DAC
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+ Startup Order :- DAC --> Mixers --> Output PGA --> Digital Unmute
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+
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+ Shutdown Order :- Digital Mute --> Output PGA --> Mixers --> DAC
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This assumes that the codec PCM output path from the DAC is via a mixer and then
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a PGA (programmable gain amplifier) before being output to the speakers.
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@@ -36,10 +38,11 @@ Capture artifacts are somewhat easier to get rid as we can delay activating the
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ADC until all the pops have occurred. This follows similar power rules to
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playback in that components are powered in a sequence depending upon stream
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startup or shutdown.
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+::
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- Startup Order - Input PGA --> Mixers --> ADC
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-
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- Shutdown Order - ADC --> Mixers --> Input PGA
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+ Startup Order - Input PGA --> Mixers --> ADC
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+
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+ Shutdown Order - ADC --> Mixers --> Input PGA
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Zipper Noise
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