TLV320AIC3268: TLV320AIC3268 Headphones Output Distortion

Hi Sirs,

We got headphones distortion with CodecControl's example configuration. With 48kHz and 44.1kHz I2S, there are 2nd and 3rd harmonics with 1kHz test tone playback, and complete distorted signal with 10kHz test tone. Would you pls advise how to configure the headphones output with no distortion all the way from 20Hz to 20kHz?

CC Configuration:


1kHz Test Tone:


1kHz FFT:


10kHz Test Tone:


10kHz FFT


Headphones Playback Example:

#############################################
# Headphone playback
# AVdd = 1.8V, DVdd = 1.8V, MCLK = 12.288MHz
# PLL Disabled, DOSR = 128, PRB_P1
# Primary I2S interface used with WCLK & BCLK as inputs to the device
#############################################



#####################################
# Software Reset
#####################################
#
w 30 00 00
w 30 7F 00
w 30 01 01
#
######################################



######################################
# Clock configuration
######################################
#
# select MCLK for CODEC clock input, bypass PLL
w 30 04 00
#
# NDAC = 1, MDAC = 2
w 30 0B 81
w 30 0C 82
#
# DOSR = 128
w 30 0D 00
w 30 0E 80
#
#######################################



###################################
# Initialize the Codec
###################################
#
# select page 1
w 30 00 01
#
# Disable weak connection between AVDD and DVDD
w 30 01 00
#
# set the REF charging time to 40 ms
w 30 7A 01
#
##################################



#######################################
# ASI #1 configuration
#######################################
#
# select page 4
w 30 00 04
#
# set ASI#1 16 bits, I2S mode
w 30 01 00
w 30 0A 00
#
#########################################




#########################################
# Signal processing
#########################################
#
# select page 0
w 30 00 00
#
# set DAC PRB mode to PRB_P1
w 30 3C 01
#
################################



#######################################################
# DAC configuration
#######################################################
#
# select page 1
w 30 00 01
#
# Set DAC PTM mode to PTM_P3
w 30 03 00
w 30 04 00
#
# Headphone in Ground-centered Mode, HPL gain = 0 dB
w 30 1F 80
#
# HPR to have independent gain, set to 0 dB
w 30 20 00
#
# Charge pump runs of Oscillator clock with divider = 4
w 30 21 28
#
# Charge pump to power up on the headphone power up in Ground-centered Mode
w 30 23 10
#
# Enable DAC to HPL/HPR and power up HPL/HPR
w 30 1B 33
#
# select page 0
w 30 00 00
#
# power up DAC_L and DAC_R
w 30 3F C0
#
# Unmute the DAC digital volume control
w 30 40 00
#
##################################################


Thank you and Best regards,

Wayne Chen
06/20/2017