Why does Premiere refuse to add all 6 Audio Channels from 6.1 Surround Sound Footage to my timeline?

[nickw29628051]

I have 6.1 Surround sound footage which I'm trying to add to the timeline in seperate channels, but Premiere refuses to add the Left channel to the timeline when I drag the clip onto the timeline? 

The left channel is there because if I modify the channels I can make the left channel appear, but premiere just wont add all 6 Channels only 5 channels.

Find screen recording here: https://youtu.be/DDCYUG9LVtc

How can I fix this?