Thanks for flagging, this will be fixed in an upcoming version of the theme. In the interim, you can edit the microphone access for the iframe as follows:
If this was the only change you made to the forked iframe-common.js file, you can upgrade your theme and delete the forked file to get the fix (this will ensure you get future theme updates to this file!). If you made other changes, you can keep your forked card with the change Rose described above.