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<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>It appears that both the echo canceller and the noise
reducer (NR) introduce rather severe clicking artifacts when presented with
audio that has slightly overloaded the A/D converters. I am talking about
speech that sounds just slightly distorted, due to clipping, when simply played
back. If I pass that speech through the echo canceller or the noise reducer, it
acquires really loud clicks and/or scratchiness in high amplitude sections.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Granted, it would be best if I could avoid any clipping in
the first place. A problem, though, is that we can not control end user
behavior and it is quite common for them to have their audio settings slightly
out of adjustment.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>I’ve found a workaround, which is to divide
everything by two before sending it to the AEC or NR.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Is this a known problem? Would it be helpful for me to
send a couple of .wav files to illustrate?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Thanks again for the great contributions.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>-<st1:GivenName w:st="on">Michael</st1:GivenName><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
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