When customizing distance values, consider the following guidelines:
ConversationalDistance is the distance from the listener at which a speaker’s voice is heard at its original volume. This must be an integer in the range 0 <= ConversationalDistance <= AudibleDistance. Consider this to be the expected close-by conversational distance. The ConversationalDistance sounds the most realistic when it's half the height of a typical speaking entity in your game.
When using the default AudioFadeModel value, if you want voice chat to naturally fade to near zero loudness at the edge of the AudibleDistance so it doesn't sound like it's being abruptly cut off, then set the AudibleDistance to a minimum of: 32 × ConversationalDistance ÷ AudioFadeIntensityByDistance.
When using the ExponentialByDistance AudioFadeModel, it's recommended that you keep the ConversationalDistance value at 1 or greater and adjust the value of the AudioFadeIntensityByDistance property based on the following formula: AudioFadeIntensityByDistance = 3 ÷ (1 + 1.75 × log10(ConversationalDistance))