Thanks to @Dawid Drozd's answer, I've created a Windows batch script that will run AVD without sound input/output. Just give the script a parameter of AVD name.
The trick is to run set QEMU_AUDIO_DRV=none
before executing AVD.
@echo off
if "%1"=="" goto usage
set QEMU_AUDIO_DRV=none
@echo Running AVD "%1" without sound...
@echo.
%ANDROID_HOME%\tools\emulator.exe -avd %1
goto :eof
:usage
@echo.
@echo -----------------------------------
@echo Usage: %0 ^
@echo -----------------------------------
@echo.
@timeout 3 >0
exit /B 1