Normally it's possible to transmitte anthing throgh RS232.
But it depends on your data baud rate .
And you had to take care in application layer to mix voice and data together at the Tx and parse the at the Rx .
of course your voice is encoded acording to your application.
you may read PCM from the voice card and forwared it to the serial port
thank you alzomor
how much is the proper speed (in bps) for desirable transmission of voice through RS232?. Is it possible to mux voice and 1200 bps data on the 56Kbps line.