Star Trek Online now has integrated Vivox voice chat since the Season 4 update.
The integrated voice chat offers two different channels. One for fleet chat and the other for team chat. When the N key (default) is pressed down it will activate your microphone.
Within each you can mute individual players in each channel by clicking on the icon next to their name when you open the "Participant List."
 Feature List
- Filter for individual players
- Ability for 2 channels, team and fleet
- Mute Out of Focus (Mutes Mic and Voice Chat when game is running in the background)
- Multi-Channel volume (Choose to hear both Fleet and Team chat or one at a time)
- Option to set voice output to device separate from STO Music/Sound
 Disabling Voice Chat
You can disable voice chat completely by going to options and then navigating to the "Voice Chat" tab. First item listed is "Disable Voice Chat," select the box then click ok to confirm.