From Forum Nokia Wiki

Q. When the G711 packets are played out, the noise is really bad. Why?

A. Try the folloing:

• Using the SetEncoderMode and SetDecoderMode functions to set mulaw.
• Check the first word of the G.711 audio buffer from the mic for the appropriate audio format. Only process those audio buffers that were "normal speech" (value of 1). Apparently some of the audio buffers contain data which is not "normal voice.

Q. Why am I getting KErrUnderflow?

A. During player initialization, make sure stat code at the call back is successful. Receiving EAPSPlayerInitComplete is not good enough. The status code at the call back needs to be checked. When sending data to the write queue when the player has not been successfully stated, KErrUnderFlow is returned.

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