[PD] Only one instance of Pd can produce sound in Ubuntu

[Matteo Sisti Sette]

Hi,

If I open multiple instances of Pd in Ubuntu (doesn't matter whether 
vanilla or extended or mixed), only the first one has sound. No matter 
whether I set "alsa" or "oss" in Media.

(btw I'm sure I had seen also "portaudio" listed but now it's gone)

Usually there's no problem in having multiple applications send sound to 
the same output device (not sure whether the same can be said about 
input)...
Is there something I'm missing that will allow multiple Pd's to send 
sound to the output just as multiple applications do?

thanks
m.