We are having problems with background hiss and a squealing sound when
playing sound through a KITSGTL5000EVBE connected to an i.mx6 MCU. After
the actual sound plays, the hiss becomes more evident and a squealing
sound is heard that changes frequency until the SGTL5000 is powered down
by Alsa. The i.MX6, which is housed on a MSC Q7 module, is running Linux
3.0.35 built from Yocto Dora with the MSC BSP layer. Other than changes
to direct the I2c control traffic to the correct muxed output, there are
no changes to sgtl5000.c or imx-sgtl5000.c.
To eliminate the possibility of the hiss and squeal being present on the
I2S data line, the i.MX6 I2S Data out line was disconnected and the
SGTL5000 I2S Data In was shorted to ground. This did not reduce the hiss
We use aplay to duplicate this issue, which occurs every time we play
any sound. For example: aplay Side_Left.wav
Has anyone experienced undesired sound artifacts when using the SGTL5000,
especially in the KITSGTL500EVBE? If so, what steps did you take to
resolve the issue?