Constant volume OSD? in 16.04

Question

Previously I was using Ubuntu Gnome, I've needed to clean boot my systems so I've gone with straight Ubuntu 16.04.

On the two systems I've reloaded I'm getting a constant volume OSD (it appears approx every 2-4 minutes).

The only thing my two systems have in common is they both share a Logitech G710+ keyboard which does have a volume rocker.

The volume rocker does work.

How can I diagnose what's causing this issue and ideally fix it. I don't want to disable the OSD as it is useful when I do actually change the volume.

Answer 1

1. You can start monitoring DBus for Notify calls, you may use this that will show you a clean output:

   dbus-monitor "type=method_call","path=/org/freedesktop/Notifications","interface=org.freedesktop.Notifications","member=Notify"
   

   Here an example of the output:

   method call time=1466117414.215345 sender=:1.45 -> destination=:1.34 serial=51 path=/org/freedesktop/Notifications; interface=org.freedesktop.Notifications; member=Notify
      string "Xfce volume daemon"
      uint32 0
      string "audio-volume-low"
      string "Volume is at 25%"
      string ""
      array [
      ]
      array [
         dict entry(
            string "value"
            variant             int32 25
         )
      ]
      int32 -1
   method call time=1466117414.215449 sender=:1.49 -> destination=:1.34 serial=2065 path=/org/freedesktop/Notifications; interface=org.freedesktop.Notifications; member=Notify
      string "indicator-sound"
      uint32 0
      string "audio-volume-low"
      string "Volume"
      string "Headphones"
      array [
      ]
      array [
         dict entry(
            string "x-canonical-non-shaped-icon"
            variant             string "true"
         )
         dict entry(
            string "x-canonical-value-bar-tint"
            variant             string "false"
         )
         dict entry(
            string "x-canonical-private-synchronous"
            variant             string "true"
         )
         dict entry(
            string "value"
            variant             int32 26
         )
      ]
      int32 -1
   

2. Check the source and destination

   Most important part is:

   method call time=1466117414.215345 sender=:1.45 -> destination=:1.34 ...
      string "Xfce volume daemon"
   ...
   method call time=1466117414.215449 sender=:1.49 -> destination=:1.34 ...
      string "indicator-sound"
   ...
   

   Open D-Feet → Session Bus: check PID & CMD for each bus address. In my example I found:

   :1.34  2891  /usr/lib/x86_64-linux-gnu/notify-osd
   :1.45  2933  xfce4-volumed
   :1.49  2963  /usr/lib/x86_64-linux-gnu/indicator-sound/indicator-sound-service
   

   

   Yep I got bobbles on each volume change one from indicator-sound-service and another from xfce4-volumed (I've Xubuntu 16.04 with Unity indicators enabled)

3. If you think that cause could be the keyboard then use: xev or better sudo evtest to monitor the X keyboard events.

Reference: https://wiki.ubuntu.com/DebuggingDBus