2.2.5.4 PidNameXVoiceMessageDuration Property
Type: PtypInteger16 ([MS-OXCDATA] section 2.11.1)
The PidNameXVoiceMessageDuration property ([MS-OXPROPS] section 2.503) specifies the length of the attached voice message, in seconds.
The relationship between this property and the X-VoiceMessageDuration MIME header is specified in [MS-OXCMAIL] section 2.1.3.2.3 and [MS-OXCMAIL] section 2.2.3.2.23.