What is com.apple.audio.SandboxHelper I'm trying to troubleshoot speech recognition dodginess.

Executing ps -ax | grep audio I get:

ps -ax | grep audio
  130 ??         2:40.49 /usr/sbin/coreaudiod
  166 ??         0:00.02 /System/Library/Frameworks/AudioToolbox.framework/XPCServices/com.apple.audio.SandboxHelper.xpc/Contents/MacOS/com.apple.audio.SandboxHelper
  168 ??         0:00.47 /System/Library/Frameworks/CoreAudio.framework/Versions/A/XPCServices/com.apple.audio.DriverHelper.xpc/Contents/MacOS/com.apple.audio.DriverHelper
 1931 ??         0:00.02 /System/Library/Frameworks/AudioToolbox.framework/XPCServices/com.apple.audio.SandboxHelper.xpc/Contents/MacOS/com.apple.audio.SandboxHelper
 1949 ttys001    0:00.00 grep audio


What is com.apple.audio.SandboxHelper?  Why would I need one, let alone two?
For what it's worth, I've been looking at an audio issue today and noticed I had 6 different instances of com.apple.audio.SandboxHelper running. Checking showed that the system thinks it has 6 different audio devices attached, so it seems each audio device get a SandboxHelper to look after it.

Oddly, no other piece of hardware, or associated drivers, has a SandboxHelper associated with it, so either the audio devices are the only ones that need help operating in a Sandbox, or only the audio driver team used that name and other tasks running in Sandboxes have their helpers called something else.