[pulseaudio-discuss] RTP delay and another problem

[Jonathan Abrams]

Hey folks,
I've been having a couple issues with RTP. I'm using pulseaudio 0.9.15.
For some background, I have a system set up where I have one machine  
running module-rtp-send, attached to the monitor of a null sink. The  
receiving machine has module-rtp-recv loaded, that then attaches to a  
null sink. This allows me to hook up applications to RTP as if it were  
any other device. So far so good!

Here are my problems:
1) When I make a connection and start to play some audio there's an  
approximately 5 second delay before audio is heard on the receiving  
end. These 5 seconds also appear to be 'lost', not just buffered. What  
could be causing this? Is this a known issue or a bug, or just how it  
normally works? Is there a workaround or fix?

2) Because I sometimes need to connect the RTP stream (being passed  
through a null sink) to a device instead of an application, I use a  
'pacat -r -d <deviceid1> | pacat -p -d <deviceid2>' loopback. This  
will sound ok for a bit, but then gaps start to appear in the audio.  
It works ok if I connect the receiving RTP sink-input stream directly  
to the intended sink, but the system we're using needs to treat the  
RTP stream as a source device (hence the null sink, and pacat  
loopback). So obviously, RTP + pacat loopback doesn't seem to work  
well together. But RTP and the pacat loopback mechanism work fine on  
their own. Any ideas?

Thanks in advance!

-Jonathan