Disable Welcome to Avast at install

I have created a custom admin.ini file that adds the following settings during install for disabling sound.

[common]
SoundsEnabled=0
SoundsVirus=0
SoundsSuspic=0
SoundsPUP=0
SoundsScan=0
SoundsUpdate=0
SoundsFirewall=0
SoundsVoiceover=0

After install is complete, “Welcome to Avast” audio is still enabled. When I look through the settings, all audio is turned off. Is there a way to silence this? We are planning on deploying this during the school day and do not this audio popping up on hundreds of computers.

It would be fun to place some webcams and stream the video so we can watch the reactions ;D

Please post/ask here: https://forum.avast.com/index.php?board=55.0