The IPC has set up a dedicated sitting volleyball live stream here: https://www.paralympic.org/rio-2016/watch-sitting-volleyball
However, the stream will only be broadcasting LIVE starting on September 15th for the final rounds of matches.
For the preliminaries, there will be a sitting volleyball report included in the overall daily summary video report of all sports, available each day on the IPC website home page here: www.paralympic.org .
You can also find daily match reports on Daily Match Reports – 1