CNA too high in ISM DTX

Coding the testvector stv4ISM48n.wav in DTX, there are added annoying noisy segments. This is due to CNA being applied on signals being initially a silence but following noisy segments. The DTX off operation is fine. I am not sure if something can be done with this signal though...

From top: DTX off synthesis, DTX on synthesis:

Command-line:

ivas_cod.exe -dtx -ism 4 scripts/testv/stvISM1.csv scripts/testv/stvISM2.csv scripts/testv/stvISM3.csv scripts/testv/stvISM4.csv 48000 48 scripts/testv/stv4ISM48n.wav bit

and binaural output.