Unable to use microphone in BBB widget

### Description

I am unable to join a BBB meeting using my microphone. It is only possible to join without microphone and only be able to listen. There is no microphone access request done from the browser.

This issue is similar to #14901.

### Steps to reproduce

- Create BBB widget
- Join meeting
- Choose to use microphone

Describe how what happens differs from what you expected:

The browser should ask which microphone to use.
The meeting should be enter-able using the microphone.

Logs send: yes

```
Firefox can’t establish a connection to the server at wss://node21.bbb.rbg.tum.de/html5client/sockjs/811/xxxxxxx/websocket. f30716b2b57e2862c4db2325b7aac63f4622842b.js:61:23114
The connection to wss://node21.bbb.rbg.tum.de/html5client/sockjs/811/xxxxxxx/websocket was interrupted while the page was loading. f30716b2b57e2862c4db2325b7aac63f4622842b.js:61:23114
WebRTC: Using five or more STUN/TURN servers causes problems sip.js:18191
Mon Jun 07 2021 12:06:11 GMT+0200 (Central European Summer Time) | sip.SessionDescriptionHandler | SessionDescriptionHandler.getDescription failed - NotAllowedError: The request is not allowed by the user agent or the platform in the current context. sip.js:9594:25
Mon Jun 07 2021 12:06:11 GMT+0200 (Central European Summer Time) | sip.Inviter | Session.getOffer: SDH getDescription rejected... sip.js:9594:25
Mon Jun 07 2021 12:06:11 GMT+0200 (Central European Summer Time) | sip.Inviter | The request is not allowed by the user agent or the platform in the current context.
```

For demonstration purposes I made the screenshot of the widget in a new tab.
The same error happens when used from the chat window itself.

### Version information

- **Platform**: web (desktop does not work as well)
- **Browser**: Firefox 89.0
- **OS**: Arch Linux
- **URL**: Private server, Element version 3a67dc18e9e3-react-3a67dc18e9e3-js-3a67dc18e9e3 (latest docker version)

Thank you very much for this awesome project.