Demystifying Mixing VoIP and Telephony in a Meeting

With Unified Voice (UV) enabled and selected from within a meeting room:

The host may choose: Meeting>Preferences>Audio Conference>Allow participants to use Microphones: When Allow participants to use Microphones is checked, participants have power to enable their own microphones within the meeting. When it is unchecked, the host must enable microphones first and then the participant can enable the microphone with host permission within the meeting:

In either case, checked or unchecked, the host needs to first start the audio conference within any meeting:

And the participant needs to choose the microphone option and enable it (even though the host has enabled it manually within the meeting or set it as permanently enabled within the room):

Note that by default, when UV is in use, the telephony option is checked for the participant:

The participant must select the microphone option in order to use the microphone instead of the phone; this will allow the microphone to broadcast to the users in the meeting using UV telephony:

With all these settings in place, VoIP microphones can talk to telephony and telephony to VoIP and both will be audible in an archive recording for playback on demand.