User's Manual

vMix User Guide
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When this is enabled, vMix will try to keep the streaming speed as close to the selected bit rates as
possible.
Note that this option may reduce the quality of the stream.
Keyframe Aligned
When sending multiple bitrates, select this option to ensure all streams are aligned on the same keyframe.
This can improve seamless switching support at the expense of slightly lower quality.
Auto Adjust
When using FMLE as the encoder, the quality of the stream can be dynamically adjusted to suit the
conditions of the internet connection.
Audio
Select the Audio encoding format to use with the stream.
MP3 is supported when using FMLE (Flash Media Live Encoder) as the encoder, while AAC is the only
option when using FFMPEG.
If you would like to use FMLE with AAC, an additional plugin needs to be purchased from MainConcept.
Audio Channels
See Output Audio Channels
Multi Bitrate Support
vMix supports Multi Bitrate streaming with both the FMLE and FFMPEG streaming applications.
There are two methods of configuring Multi Bitrate depending on the requirements of your streaming provider.
Please check with your streaming provider if you are unsure.
Single Stream Key
1. Select your streaming provider from the Destination dropdown box under stream 1.
2. Configure the first stream bitrate from Quality.
3. Configure up to two additional streams by selecting Stream 1 Multi-Bitrate as the Destination for
stream 2 and optionally stream 3.