We posed this same question to the 8x8 gurus, and the clunky methodology below was their recommendation (I'm just copying and pasting that part of our procedure). If anyone has a better way, we're all ears!
Create an .mp3 audio file.
a. Browse to https://ttsmp3.com/.
b. Select voice from drop-down.
i. Currently, US English = Kendra & Spanish = Mia.
c. Type in username.
d. Click "Download as MP3."
e. Browse to downloaded file, and rename as desired.
i. Current format is "8x8 DBN firstinitial+lastname.mp3."
f. Log into the 8x8 Admin Console.
g. Click Users.
h. Click the Edit icon for the desired user.
i. Click "Voicemail settings."
j. In the "Voicemail name and last name" section, follow the prompts to add the created .mp3 file.
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Ed Heller
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