Bug#834437: gnome-control-center does not show HDMI sound (Debian stretch)

[nicesw123]

Package: gnome-control-center
Version: 1:3.20.1-2
Severity: normal

Dear Maintainer,

(I'm running Debian strech [=testing])

The Gnome-based sound configuration no longer shows HDMI sound.

(I ONLY see Build-in Audio Analog Stereo).

But
aplay -D plughw:0,3 /usr/share/sounds/alsa/Front_Center.wav
does play sound through HDMI.

What can I do to get HDMI listed in the Gnome Sound Config??

Note: this has been a problem now from a few months. I'm only reporting the issue now.
Might be similar to bug #820558 ( https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=820558 ), but I NEVER see the HDMI audio.

Thanks for any help or suggestions.
n.

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.6.0-1-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gnome-control-center depends on:
ii  accountsservice            0.6.40-3
ii  apg                        2.2.3.dfsg.1-3
ii  colord                     1.3.2-1
ii  desktop-file-utils         0.23-1
ii  gnome-control-center-data  1:3.20.1-2
ii  gnome-desktop3-data        3.20.2-1
ii  gnome-settings-daemon      3.20.1-2
ii  gsettings-desktop-schemas  3.20.0-3
ii  libaccountsservice0        0.6.40-3
ii  libatk1.0-0                2.20.0-1
ii  libc6                      2.23-4
ii  libcairo-gobject2          1.14.6-1+b1
ii  libcairo2                  1.14.6-1+b1
ii  libcanberra-gtk3-0         0.30-3
ii  libcanberra0               0.30-3
ii  libcheese-gtk25            3.20.2-2
ii  libcheese8                 3.20.2-2
ii  libclutter-1.0-0           1.26.0-2
ii  libclutter-gtk-1.0-0       1.8.0-1
ii  libcolord-gtk1             0.1.26-1
ii  libcolord2                 1.3.2-1
ii  libcups2                   2.1.4-4
ii  libdbus-glib-1-2           0.106-1
ii  libfontconfig1             2.11.0-6.5
ii  libgdk-pixbuf2.0-0         2.34.0-1
ii  libgl1-mesa-glx [libgl1]   11.2.2-1
ii  libglib2.0-0               2.48.1-2
ii  libgnome-bluetooth13       3.20.0-1
ii  libgnome-desktop-3-12      3.20.2-1
ii  libgoa-1.0-0b              3.20.3-1
ii  libgoa-backend-1.0-1       3.20.3-1
ii  libgrilo-0.3-0             0.3.1-1
ii  libgtk-3-0                 3.20.7-1
ii  libgtop-2.0-10             2.34.0-1
ii  libgudev-1.0-0             230-3
ii  libibus-1.0-5              1.5.11-1
ii  libkrb5-3                  1.14.3+dfsg-1
ii  libmm-glib0                1.6.0-1
ii  libnm-glib-vpn1            1.2.2-2
ii  libnm-glib4                1.2.2-2
ii  libnm-gtk0                 1.2.4-1
ii  libnm-util2                1.2.2-2
ii  libpango-1.0-0             1.40.1-1
ii  libpangocairo-1.0-0        1.40.1-1
ii  libpolkit-gobject-1-0      0.105-16
ii  libpulse-mainloop-glib0    9.0-1.1
ii  libpulse0                  9.0-1.1
ii  libpwquality1              1.3.0-1
ii  libsmbclient               2:4.4.5+dfsg-2
ii  libsoup2.4-1               2.54.1-1
ii  libupower-glib3            0.99.4-3
ii  libwacom2                  0.19-1
ii  libx11-6                   2:1.6.3-1
ii  libxi6                     2:1.7.6-1
ii  libxml2                    2.9.4+dfsg1-1+b1

Versions of packages gnome-control-center recommends:
ii  cracklib-runtime              2.9.2-1+b2
ii  cups-pk-helper                0.2.6-1
ii  gkbd-capplet                  3.6.0-1
ii  gnome-online-accounts         3.20.3-1
ii  gnome-user-guide              3.20.2-1
ii  gnome-user-share              3.18.1-1
ii  iso-codes                     3.69-1
ii  libnss-myhostname             230-7
ii  mesa-utils                    8.3.0-1
ii  mousetweaks                   3.12.0-1
ii  network-manager-gnome         1.2.4-1
ii  policykit-1                   0.105-16
ii  pulseaudio-module-bluetooth   9.0-1.1
ii  realmd                        0.16.2-2
ii  rygel                         0.30.3-1
ii  rygel-tracker                 0.30.3-1
ii  system-config-printer-common  1.5.7-2

Versions of packages gnome-control-center suggests:
ii  gstreamer1.0-pulseaudio  1.8.2-1
pn  libcanberra-gtk-module   <none>
ii  libcanberra-gtk3-module  0.30-3
ii  x11-xserver-utils        7.7+7

-- no debconf information