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Full Version: Audio transmission over network
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I am sure someone already did some research into this, but the search of the forum and/or google did not help me a lot.
My situation at home - I have an overhead projector with HDMI input, but no audio output.
Currently, I am using Creative SB external with SPDI/F for audio and I have a long wire to the receiver next to the screen. This causes drop-outs and so on.
What I am looking for is a solution, where I can stream the actual audio from the playing movie over ethernet to a different client PC connected to the receiver.
This would allow me to play the video using let's say Raspberry Pi next to projector and audio using second Raspberry Pi next to the receiver.
Unfortunately, my experimetns with pulseaudio did not work correctly - after a short time the audio had lags, lots of jittering and so on (seems like there is a huge requirement for both network throughput and CPU usage).
Is there any other setup I can try?
I was experimenting with jack server, but I was not able to make a working setup (stupid me...).
Thanks for any advice.
I think you will always have sync issues doing this
I've noticed some bugs in the pulseaudio network code, it's based on both system clocks running almost exactly synchronized, and if one is offset from the other that translates into a similar a/v sync error.
Furthermore, there was a bug that if one machine's clock was too far ahead of the other one, the audio delay calculated by pulseaudio would become negative, which would then be casted to unsigned int64_t somewhere (I couldn't find where exactly) which would lead to gigantic sync errors.

The best way I've had this work is, use a wired network, install ntp on both machines, then set the default pulseaudio server in /etc/pulse/client.conf or use the PULSE_SERVER environment variable before starting XBMC.
Thanks for the suggestions.
Actually, I did some more testing into pulseaudio and I found, that the ntp server is essential for its usage.
But still, it requires lots of CPU power on the transmitting machine, which is a surprise for me Sad
I wouldn't have expected otherwise, decoding uses the most cpu, writing the audio to the soundcard hardly uses any cpu.