I build from svn trunk 7906, configured --without-sound, and in order to get things operational, had to add a
hidden_options["sound_source"] = None
Otherwise python complains about accessing this attribute later on around line 670ish.
I have no clue if that's the right fix.
It is totally the right fix and has been applied in r7920. Thanks!
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/709