buzz witn usb audio card when fancontrol daemon polls temps

Hello,

On one hand, I have installed fancontrol 1:3.4.0-2 in Ubuntu 16.04 LTS

After running pwmconfig, the following /etc/fancontrol configuration file is created:

# Configuration file generated by pwmconfig, changes will be lost
INTERVAL=10
DEVPATH=hwmon1=devices/pci0000:00/0000:00:01.0/0000:01:00.0 hwmon2=devices/platform/coretemp.0 hwmon3=
DEVNAME=hwmon1=radeon hwmon2=coretemp hwmon3=dell_smm
FCTEMPS=hwmon3/pwm2=hwmon1/temp1_input hwmon3/pwm1=hwmon2/temp1_input
FCFANS=hwmon3/pwm2=hwmon3/fan2_input hwmon3/pwm1=hwmon3/fan1_input
MINTEMP=hwmon3/pwm2=60 hwmon3/pwm1=60
MAXTEMP=hwmon3/pwm2=100 hwmon3/pwm1=90
MINSTART=hwmon3/pwm2=150 hwmon3/pwm1=150
MINSTOP=hwmon3/pwm2=100 hwmon3/pwm1=100
MINPWM=hwmon3/pwm2=0 hwmon3/pwm1=0
MAXPWM=hwmon3/pwm2=255 hwmon3/pwm1=255

On the other hand, I've got an usb sound card : USB [Scarlett 2i4 USB]

When listening to music or any sound event, there is regular buzz in the sound with periodicity as in parameter INTERVAL in file /etc/fancontrol.

In other terms, each time fancontrol daemon polls the temperatures there is a buzz in the sound emitted by the usb sound card.

I've recorded a sample of this buzz for INTERVAL=1
http://www.sekisushai.net/usb_buzz.wav

The problem persists even if I change the usb port of the sound card. However the problem doesn't exist with the internal audio chipset of the laptop or when fancontrol daemon is off.

Any ideas on how to solve this ?

Thank you