Client sync on Audio only streaming on Wifi LAN

[Angus Margerison]

Hello all,

Can anybody give me any tips on how to set up Janus to stream audio to clients on a Wifi LAN to ensure the best synchronisation on client mobile phones. Curently I can have identical phones with identical browsers and operating systems in roughly the same place, but there can be 500-1000ms difference in the playout times. By looking at the packets in wireshark I can see that the UDP packets are Unicast.

Here is my streaming plugin config:

gstreamer-sample: {

type="rtp"

id = 1

desription = "local audio stream"

audio = true

video = false

audioport =5002

audiopt = 111

audiortpmap = "opus/48000/2"

Any tips, ideas, signposts or links would be most appreciated

Thank you Janus ...its amazing.

Best

Angus

[Alessandro Toppi]

Packet will always be delivered through unicast since webrtc mandates SRTP-DTLS e2e encryption.
As of the synchronization among the peers that you are trying to achieve, that is not an easy task.
Every peer connection (client <-> janus) has an isolate context and any change in the stack status (from the wifi to RTP decoders) will affect the playout, so deltas <1 sec are definitely expected in general. 

[Angus Margerison]

Thank  you very much for that reply.

Angus