Syncing two live sources

[Michael MacIntosh]

You should be able to share the clock between the two pipelines that are 
doing the transcoding, the receivers should then play the two streams at 
the same time.  But there are a lot of variables involved, more than 
likely you would play both streams as the transcoder "saw" them.  If one 
source is inherently higher latency than the other, they might not 
appear in-sync.

Alternatively you could just make both of the pipelines inside of one 
pipeline, that should handle the syncing for the transcoder. Assuming 
you don't want to control both streams independently.

Cheers.