Making an Arduino USB Mute Button for Online Meetings

You can control the mute in software using the Arduino USB keyboard library, then just send the appropriate key combination when the button is pressed:

For MS Teams, you send Ctrl+Shift+M (Cmd+Shift+M for Mac) For Google Meet you send Ctrl+D (Cmd+D for Mac) For Zoom, you send Alt+A (Cmd+Shift+A for Mac)

Note that unlike Telephony devices, which can return the status of the mute on the computer, there is no way to tell if the software itself is muted.

I tried it in MS Team web call, and Zoom web call, neither of them seem to do WebHID, so I didn't find any option to enable similarly as in Google Meet. I guess Meet has to do this, as they don't have desktop version themselves.

On the other hand, looking at MS Team & Zoom desktop apps (in MacOS), there are some options that suggest that _some_ sort of USB hacking would be possible.

Teams > Settings > Devices > Sync Device Buttons; and Zoom > Preferences > Audio > Sync buttons on headset seem to be the key to enable that, but it's unclear just now what sort of device are they looking for.

I'm guessing it can be the "General Desktop Page 0x01" / "Call State Management Control 0x13" kind of device, as briefly mentioned in the blogpost, with the Call Mute Toggle 0xE1. It's a different kind of value (changes on a signal edge) rather than absolute like the button done here, and would need a bit more experimentation to send the right kind of signal. My initial checks are inconclusive.

Looking at MS Presenter+, it seems like the button behaviours can be customized by software, so I wonder how much of its behaviour is hardware devined. Also, it's Bluetooth, so likely the control mechanism is different from this USB-based control.

Thanks for the question, though, the rabbit hole goes deeper!