Audio is not playing during notification

[macbeto]

Hi:
I moved from Linux Mint 20.1 to 20.3 and now I noticed that the audio of the notification is not playing properly.
It is not a problem with the audio file (wav) or with the python script, because when I execute the python script it doesn't play, but if I execute it again in a short time it execute well with the audio as many times as I execute it.
My version is notify-py==0.3.42
The logging shows:
lixbeto2@lix:/Beto$ ./PurgarSSD.py
2023-10-10 19:35:46.893 | INFO | notifypy.notify:init:50 - Logging is enabled.
2023-10-10 19:35:46.897 | INFO | notifypy.os_notifiers.linux::16 - libnotify found, using it for notifications
2023-10-10 19:35:46.897 | DEBUG | notifypy.os_notifiers.linux:send_notification:74 - Generated command: ['/usr/bin/notify-send', 'Purgado de Disco Duro', 'Comienza el Purgado (shred) del Disco Duro', '--icon=/home/lix/Beto/Iconos/Archivos.png', "--app-name='Python Application (notify.py)'", '-u', 'normal']
2023-10-10 19:35:46.907 | INFO | notifypy.notify:send_notification:351 - Sent notification.
lixbeto2@lix:/Beto$ ./PurgarSSD.py
2023-10-10 19:35:47.879 | INFO | notifypy.notify:init:50 - Logging is enabled.
2023-10-10 19:35:47.882 | INFO | notifypy.os_notifiers.linux::16 - libnotify found, using it for notifications
2023-10-10 19:35:47.883 | DEBUG | notifypy.os_notifiers.linux:send_notification:74 - Generated command: ['/usr/bin/notify-send', 'Purgado de Disco Duro', 'Comienza el Purgado (shred) del Disco Duro', '--icon=/home/lix/Beto/Iconos/Archivos.png', "--app-name='Python Application (notify.py)'", '-u', 'normal']
2023-10-10 19:35:47.895 | INFO | notifypy.notify:send_notification:351 - Sent notification.

The first time it didn't play, but the second it played well.
Does it mean I have some kind of problem with libnotify app? It is 0.7.9 release.