core-dump with pulseaudio 12.0

[oberon-manjaro]

Since update to pulseaudio 12.0, when pressing vol+ or vol- I get

Assertion 'pa_channels_valid(channels)' failed at pulse/volume.c:74, function pa_cvolume_set(). Aborting.
Aborted (core dumped)

When trying to mute volume I get

pa_context_set_sink_mute_by_index() failed

[tvieregge]

I'm getting the same issue with pulseaudio 12.2 in Manjaro.
Using pa-applet version 1.0.2-2.

[selurvedu]

This seems to be fixed in Manjaro.