Cinnamon: No sound in pretty much every GNOME game

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• Cinnamon 4.0.9
• Ubuntu 19.04
• NVIDIA GeForce GTX 980 (proprietary 430.26)
• 64 bit
• Due to privacy concerns, I cannot attach the whole syslog but this log was observed upon starting "sol":

Jun 26 15:53:14 toasteroven cinnamon[2734]: Did not find double property 'opacity'
Jun 26 15:53:16 toasteroven cinnamon[2734]: message repeated 181 times: [ Did not find double property 'opacity']
Jun 26 15:53:17 toasteroven /usr/lib/gdm3/gdm-x-session[2454]: Cinnamon warning: Log level 128: posix_spawn avoided (fd close requested)

```

Issue

No sound in any GNOME game.

Steps to reproduce

Launch any GNOME game. I tried sol (AisleRiot Solitaire) and quadrapassel. Do anything that would normally cause sound to play (moving cards in the case of sol, and moving or setting down pieces in the case of Tetri- err... quadrapassel)

Expected behaviour

Working sound.

Other information

There is no entry in the applications tab of the sound options for any of the games I tested. Sound is enabled on all of them.

I'm using embrosyn/cinnamon PPA, but I've observed this issue with self-compiled builds as well, and there's a Launchpad issue, although for the wrong package, as sound works fine in other desktop environments. It's also reported on an older version of Cinnamon. If you need more information, let me know.