[Solved]Playing sound after exiting letter

[Spelos]

Unfortunately, the whole point of GUI sound is that it is played along with the GUI layer.

Using PlaySoundAtEntity is your best bet.
You can modify the volume in your .snt file
or perhaps even edit the source .ogg file with some software like Audacity.

You can also play the sound at "Player" instead of an entity to make it as loud as GUI sound. (if the .snt file doesn't cap it)

Now, Mudbill's solution DOES work. But I would argue that it's not the cleanest way. Consider using PlaySoundAtEntity with your sound tweaked a little in a single line instead of timers.