Hi Nassim (@nfarfhat),
We have tried to do something similar in this discussion some time ago. Problem is that the dashboard's audio-out node can only play a single audio buffer (of finite length), for example an mp3 file. What we wanted to do is play an infinite audio stream, like a microphone.
However web audio (which is used by the audio-out node) currently doesn't support (infinite) audio streaming. So I have done a large series of experiments to workaround that. At the end I had a solution that worked fine on desktop browsers: we had good quality audio streaming in the Node-RED dashboard. But unfortunately on mobile browsers (like Chrome on Android) there was a lot of annoying distortions between the audio chunks. Couldn't get rid of that, so I gave up at the end.
Remark: a few days ago I have published a beta version of my node-red-contrib-wav-beta node, which I had originally developed for all above experiments. Saw last week by accident that this node contained a bug: the length of the chunks was incorrectly calculated, so 'perhaps' that was the reason why the audio chunks were not nicely appended by my Chrome on Android (which will cause distortions). But that is only a wild guess, and I have no time at the moment to test that theory ...
Bart
