How to remove Voxal Virtual Device from my Audio Input?

So I installed a voice changer called Voxal, it wasn't really for me so I decided to Uninstall it by simply putting it into the trash. But I keep being bothered by how the audio input sometimes changed back to Voxal.

I tried finding their official uninstaller .pkg but I can't seem to find anything useful. I tried to search through apple discussion if someone had the same problem as me. There's people who is troubled by this and instead they use an app called OSX Uninstaller but I need to pay for it. I tried looking through /Library/Extensions , /Library/Audio/Plug-ins/HAL and still found nothing that could fix this issue. Please help me, this really bothers me.