Play sound from Jenkins script

I run Jenkins on Ubuntu Mate on a Raspberry Pi 2 which has sound hardware (via HDMI).

When connected via SSH, sounds works great.

However, it does not work via Jenkins. I tried an espeak 'hi', the build succeedes, but it does not actually produce any sound at all in the speakers.

I assume the current behavior is the default Jenkins behavior, but I would like to be able to play audio files during the build (every hour).

How can I do that?

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Output of the pulse processes:

# WORKING :: When connected via SSH
jenkins   1461  0.5  1.1 144876  9652 ?        Ssl  17:53   0:00 /usr/bin/pulseaudio --daemonize=no --log-target=journal
lightdm   1477  0.7  1.2 155872 11348 ?        S<sl 17:53   0:00 /usr/bin/pulseaudio --daemonize=no --log-target=journal
ionicab+  1596  1.2  1.3 155984 11572 ?        Ssl  17:54   0:01 /usr/bin/pulseaudio --daemonize=no --log-target=journal

# NOT WORKING :: When running from Jenkins and not connected via SSH
jenkins   1461  0.1  0.6 144876  5824 ?        Ssl  17:53   0:01 /usr/bin/pulseaudio --daemonize=no --log-target=journal
lightdm   1477  0.2  0.8 155872  7092 ?        S<sl 17:53   0:01 /usr/bin/pulseaudio --daemonize=no --log-target=journal

# WORKING :: When running from Jenkins and connected via SSH
jenkins   1461  0.1  0.6 144876  5568 ?        Ssl  17:53   0:01 /usr/bin/pulseaudio --daemonize=no --log-target=journal
lightdm   1477  0.1  0.7 155872  6852 ?        S<sl 17:53   0:01 /usr/bin/pulseaudio --daemonize=no --log-target=journal
ionicab+  2271 12.5  1.2 156108 11124 ?        Ssl  18:05   0:00 /usr/bin/pulseaudio --daemonize=no --log-target=journal
jenkins   2345  0.0  0.0   9636   492 ?        S    18:05   0:00 grep pulse