In some streaming scenarios, the source audio stream might switch between stereo and mono. In Wowza Streaming Engine™ media server software, the Transcoder by default assumes that the number of audio channels doesn't change during a transcoding session. However, you can add a parameter to a Transcoder template to instruct Transcoder to force any mono audio frames to stereo by duplicating the mono stream for both the left and right channels.
To enable this feature in a Transcoder template, add the following section to the <Decode> block of the template:
<Audio> <Parameters> <Parameter> <Name>default.scaleChannels</Name> <Value>2</Value> <Type>Long</Type> </Parameter> </Parameters> </Audio>