LTSP | Sound in rdesktop sessions

Posted in: technology. Tagged: linux, ltsp, sound, rdp

Today I discovered that since our upgrade to LTSP5, sound has stopped working in rdesktop sessions. Worse, it bombs users out of their Windows session with the error:

rdesktop: pcm_params.c:2351: sndrv_pcm_hw_params: Assertion `err >= 0' failed.
Aborted

Under 4.2 it was working beautifully simply by prefixing rdesktop with esddsp, e.g.

$ esddsp rdesktop -r sound:local 192.168.0.1

But removing esddsp or replacing with padsp causes exactly the same error message. I suspect with alsa the esddsp/padsp fix is no longer required, but why does it not work?

I have even tried pointing padsp at the client pulseaudio device…

$ padsp -d -s 192.168.0.41:4713 -n rdesktop rdesktop -r sound:local 192.168.0.1

I have posted this as a question on the LTSP Mailing List and am hopeful of a solution!