Error - MinimStreamer: transcode setting '*:L16' requires a converter

[RobA]

Hi Simon,
To be able to use MinimServer on the NAS I had to delete *:L16 (that was highlighted in red) from stream.transcode. I was then able to stream the music files I wanted, in this case FLAC.
When I try to re-enter *:L16 into stream.transcode it is highlighted in red. The streamer.converter field in Properties is empty.
The MinimServer/Opt/bin folder on the NAS is empty. I can't see any ffmpeg files in any of the MinimServer folders.
Do I need to download these from somewhere?

Thanks
Rob