How to determine audio input options?

[Richard Gaskin]

The recordInput global property can be set to any of these values:

imic - records from the internal microphone
emic - ecords from the external sound input jack
cd   - records from an internal CD player
irca - records from an RCA input jack
tvfm - records from an FM radio tuner
idav - records from a DAV analog input port
mbay - records from a media-bay device
modm - records from the modem
zvpc - records from zoom video input
none - does not record.

That's cool and all, but many of those options don't exist on my system.

I tried searching the Dictionary for something like soundSources or 
soundInputs, and came up empty.

Do we have a way to determine which of those options accepted by the 
recordInput property actually exist on the current system?

--
  Richard Gaskin
  Fourth World
  Rev training and consulting: http://www.fourthworld.com
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