Wirecast™
Version 3.5.8
Media Capabilities — MPEG-1 Audio

Audio may not play

Some old types of MPEG movies (MPG, M1V) may not play audio in Wirecast.

This is a well documented issue with QuickTime (which Wirecast uses for playback of MPEG).

Workaround

The work around is to convert the media into a different type (such as MPEG-4).