Archived:Full duplex with PCM16 codec produces echo on Nokia N95 with AD-54 headset (Known Issue)

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Article Metadata
Tested with
Devices(s): Nokia N95, Nokia N95 8GB
Platform(s): S60 3rd Edition, FP1
S60 3rd Edition FP1
Created: User:Technical writer 1 (19 Jun 2008)
Last edited: hamishwillee (21 Jun 2012)


Simultaneous audio playback and recording (full duplex) may result in echo and/or feedback loop when certain wired headsets are attached and audio is being streamed in uncompressed PCM16 format.

How to reproduce

The example application S60 Platform: Full-Duplex Audio Example supports four codecs: AMR, G.711, G.729, and iLBC.

With the following modifications, also support for PCM16 format can be added:

// Specify PCM16 fourCC as follows:
fourCC = TFourCC(' ', 'P', '1', '6');
// Sample rate:
conf.iRate = EMMFSampleRate16000Hz;
// Buffer size:
const TUint KBufferLength = 0x2000;

Running full-duplex audio with this configuration works fine on most devices, but produces echo on the Nokia N95 when used with the AD-54 headset.


No solution exists.

This page was last modified on 21 June 2012, at 06:24.
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