pub const VOLUME_UNCHANGED: u8 = 0xFF;Expand description
The value that means “leave this one alone” in a volume or mute field.
It is not a level and not a mute state. A device reads it as “do not change”, and the right channel additionally as “no such channel”, so a decoder that surfaces it as a volume of 255 or as a muted pair reports a setting the sender was declining to touch.