Synced clip doesn't play in the Media window

I'm syncing a feature at the moment and often have to manually sync external sound to the clips. I can play the video in the Media viewer (on the MEDIA page) to find the sync point, but the moment I link the external audio to the video the video won't playback so I have to go to the EDIT window to see if the sync is correct.
I guess this is a bug?
Anybody have a workaround, or similar experience?
Thanks,
Eric
(I'm using 17.2.2)