Can I dynamically modulate the volume envelope of a sound channel while it is playing ?
If you alter the envelope, the envelope may restart (or at least jump), and there are some things you need to take into account. However, if you force the envelope to be off (direction up, speed 0), you can easily make software envelopes by modulating the high nybble. Sometimes there is some small noise associated with this technique, however… (Info from Jeremy Evers.