maximize noise reduction

I am also interested in this tried tunning any available parameter from

with close to a zero change in the noise level.
I tried with this as the background noise which is quite stationary and I expected some change in the noise levels but didn’t notice almost any difference.

Used arecord to record the a wav file

arecord --device=hw:1 --format=S16_LE 1.wav

and here are all the parameters I tried

~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN
GAMMA_NN: 1.100000023841858
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 0
GAMMA_NN: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 1
GAMMA_NN: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 2
GAMMA_NN: 2.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 3
GAMMA_NN: 3.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 4
GAMMA_NN: 1.100000023841858
~/src/../usb_4_mic_array $ ^C
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 0
GAMMA_NN: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 1
GAMMA_NN: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 2
GAMMA_NN: 2.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 3
GAMMA_NN: 3.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 0
GAMMA_NN: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN_SR 
GAMMA_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN_SR 1
GAMMA_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN_SR 2
GAMMA_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN_SR 3
GAMMA_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN_SR 0
GAMMA_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS
GAMMA_NS: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 0
GAMMA_NS: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 1
GAMMA_NS: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 0
GAMMA_NS: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 1
GAMMA_NS: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 2
GAMMA_NS: 2.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 3
GAMMA_NS: 3.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS_SR 
GAMMA_NS_SR: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS_SR 0
GAMMA_NS_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS_SR 1
GAMMA_NS_SR: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NS 1
GAMMA_NS: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN 1
GAMMA_NN: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py GAMMA_NN_SR 1
GAMMA_NN_SR: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py VOICEACTIVITY
VOICEACTIVITY: 0
~/src/../usb_4_mic_array $ sudo python3 tuning.py VOICEACTIVITY 1
Traceback (most recent call last):
  File "tuning.py", line 197, in <module>
    main()
  File "tuning.py", line 186, in main
    dev.write(name, sys.argv[2])
  File "tuning.py", line 77, in write
    raise ValueError('{} is read-only'.format(name))
ValueError: VOICEACTIVITY is read-only
~/src/../usb_4_mic_array $ sudo python3 tuning.py NONSTATNOISEONOFF
NONSTATNOISEONOFF: 1
~/src/../usb_4_mic_array $ sudo python3 tuning.py NONSTATNOISEONOFF_SR
NONSTATNOISEONOFF_SR: 1
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN
MIN_NN: 0.30000001192092896
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN 1
MIN_NN: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN 0
MIN_NN: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN 1
MIN_NN: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN_SR
MIN_NN_SR: 0.30000001192092896
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN_SR 0
MIN_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN_SR 1
MIN_NN_SR: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NN_SR 0
MIN_NN_SR: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NS
MIN_NS: 0.15000000596046448
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NS 0
MIN_NS: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NS 1
MIN_NS: 1.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NS 0
MIN_NS: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NS 0
MIN_NS: 0.0
~/src/../usb_4_mic_array $ sudo python3 tuning.py MIN_NS 1
MIN_NS: 1.0