Preloading of Sounds

This post has a wealth of information about sounds and how to play with the settings: https://tiltaudio.com/2020/12/22/a-word-on-sound/

The new detached preloading sometimes creates sound crackling while loading sounds. The reason for this is basically buffer underruns in the sound output from the ALSA subsystem, caused by the way the preloading works for some sound formats.

To get around these problems and speed up the start (including the preloading) significantly, you must convert your sound pack sounds in output format (44.2kHz, stereo WAV).

This is really important as it improves the speed of preloading OGG vs WAV on an PI3 by a factor of 50 (18500ms vs 330ms for 205 sounds in my latest test). So basically, if you have the matching sound format, the board is ready instantly after start.