diff --git a/sound/sound-font-config.ini-configuration.md b/sound/sound-font-config.ini-configuration.md
index 2e61140..2119e9c 100644
--- a/sound/sound-font-config.ini-configuration.md
+++ b/sound/sound-font-config.ini-configuration.md
@@ -13,8 +13,10 @@ This page explains the parameters that are available in a sound font's `config.i
 humStart=100
 
 # From ProffieOS 7.x, you can use ProffieOSHumDelay to specify how many milliseconds
-# from the beginning of "out" to start the hum. If both ProffieOSHumDelay and humStart
+# from the beginning of out.wav to start the hum. If both ProffieOSHumDelay and humStart
 # are specified, then ProffieOSHumDelay is the one that will count.
+# If not specified or set to 0 (no delay), humStart will be used instead.
+# Defaults to -1.
 ProffieOSHumDelay=-1
 
 # The volume of the hum sound. Can be 0-16, where 0 is muted.