The on NOSOUND event triggers when a user sends a Sound Request to play a sound and you do nothave that sound.
Format: on <level>:NOSOUND:<commands>
Example: on 1:NOSOUND:/notice $me Oops, $nick has $filename and I do not!
on 1:NOSOUND:/msg $nick ! $+ $nick $filename
This triggers when you do not have the requested sound. $filename refers to the name of the file that was requested.
Note: This will trigger whether the Warn if sound does not exist option is turned on or off.