Unfortunately I sneaked in a move of the gvc_mixer_control_open() call from
earlier in the function to the end of the function with commit 2152899354.
That change didn't actually move the call though, but introduced a second
call instead, leading to a critical error on opening of the sound panel.
Fix it by removing the first call to gvc_mixer_control_open() and keeping
the second one around. We want to keep the second one instead of the earlier
one because the signal handlers should be connected before we initialize gvc
and it connects to pulse, emitting all the input/output-added signals etc.
The reason why this wasn't broken before was likely because the connection
to pulse happens async, and therefore the initial emission of the signals
would effectively still have happened after we connected our handlers.
Fwiw, calling gvc_mixer_control_open() after
cc_volume_slider_set_mixer_control(), cc_subwoofer_slider_set_mixer_control()
and cc_device_combo_box_set_mixer_control() is not a problem, as those
functions all call into gvc to get static values (and as explained above,
at this point gvc wouldn't have established connection to pulse anyway).
Reported-by: Matthijs Velsink <mvelsink@gnome.org>
Fixes: 2152899354 ("sound: Listen to signals from GvcMixerControl only in sound panel")
4afd08e234