How can I determine if a sound is playing? [AS3]

How can I determine if a sound is playing? [AS3]

I need to determine if a sound is currently playing in a particular SoundChannel.
I need this since I call a function using onEventComplete to manage initiation of playback in two related sound channels, SC_A and SC_B.

In essence, when the latest sound has been completed in either SC_A or SC_B, I wish to call this function and start a new sound in the SC that completed.

Thus, if a sound in SC_A is currently playing, I wish to start the next parallell sound in SC_B and vice versa.

What property can I use to get this info? :stare:

Please advice,

Jaxz