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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal>I’m using AEC for a VoIP application on mobile
handsets. I am doing experiments to learn how to work with it, and I have a
problem:<o:p></o:p></p>
<p class=MsoNormal>As long as I play through the device’s normal speaker
and record using the mic, I have absolutely no clock drift (according to echo_diagnostic.m).
The echo is being cancelled and all is fine. Once I route to the earpiece (and
still use the mic, which is the only option), no echo is cancelled and the
diagnostic shows that I have clock drift.<o:p></o:p></p>
<p class=MsoNormal>I know that the AEC expects a locked clock, but that’s
my current situation and I couldn’t find any way to record from the same earpiece
soundcard (or whatever the internal implementation is). <o:p></o:p></p>
<p class=MsoNormal>Is there a good way for compensating for that?<o:p></o:p></p>
<p class=MsoNormal>Could you also explain more thoroughly the concept of clock
drift, as I couldn’t find much detail about it?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks!<o:p></o:p></p>
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