NEC UNIVERGE SV9100 Features And Specifications page 1330

A station can receive only one Voice Over at a time.
A multiline terminal user cannot answer a Voice Over with an internal call on hold.
An attempt to Voice Over a station can be denied if the station is in DND (Do Not Disturb)
Mode, Automatic Redial is activated, during Station Programming, during Incoming
Ringing, during Internal/External Paging, during a Conference Call, during a conference
call on hold, the terminal is on internal hold, or the terminal has a call on internal hold.
When a single line telephone is on a call and Voice Over is presented, the single line
telephone cannot talk back to the party that originated the Voice Over.
Voice Over to a single line telephone is not recommended because cross talk is inherent in
the side tone of analog telephones.
Voice Over to a user on speakerphone is not recommended because the conversation may
be heard by the outside party.
Answering a Voice Over requires a uniquely programmed Voice Over key.
Default Settings
Disabled
System Availability
Terminals
All Multiline Terminals and Single Line Telephones
Required Component(s)
None
Related Features

Conference

Off-Hook Signaling

Programmable Function Keys
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