Auto receptionist

Hi, @Zs1,

First, keep the link to this Zoom Support article titled “Using the audio library to customize audio” for future reference – it’ll come in handy:

https://support.zoom.us/hc/en-us/articles/4402414203533 

In there it recommends going through the upload process and seeing the online info for details about the requirements.  Having done that, it's helpful, but doesn't really answer your question:

I've always uploaded .WAV files.  My suggestion would be to record one brief announcement in whatever format you're most comfortable with then upload it and test it. 

Bonus Info:

"Try it and test it" is always my first approach. You can't really damage anything!  Set up a separate Auto Receptionist (edit the extension number if you want to put it somewhere where most people won't accidentally dial it):

Then change the default handling from "Route to IVR" to "Message" and upload your test file to the Audio Library there:

Then you can dial that extension (812 above) from any Zoom Phone and see if it sounds okay - you may need to wait a few minutes for the changes to take effect. (Set the Greeting Prompt from the Business Hours section to Disable... or you could set the greeting to your audio... but then then Route To Message section still needs something in it... so I recommend disabling the Greeting and using the Message area to test your audio.)

Thank you!!!