> Version of AE 2014 is 184.108.40.206.
Why? The current version is 13.2. There have been _many_ bugs fixed in the updates since then, including bugs fixed in the Mercury Transmit features for external video preview.
I'm not the expert on Mercury Transmit, but I've forwarded this forum thread to the person who is.
You will need to update your Blackmagic Desktop Video software. Version 9.8 pre-dates After Effects CC 2014 and doesn't support it as a Mercury Transmit host. I recommend updating to the most recent release, 10.4, as Blackmagic added fixes for using non-standard frame formats, a very common workflow with After Effects.
And, yes, you should install the After Effects CC 2014.2 (13.2) update.
I'll definitely install the BlackMagic update.
Regrrettably, I probably will not be able to install the AE update. Our company made a deal with Adobe that has them giving one massive update file to our IT people, who eventually roll it out to us months and months later. We are not able to simply update from the cloud. Moreover, it requires a full uninstall and new install, per IT. So we also get to lose, then restore/rebuild any customizations, presets, etc., with every update.
Interesting that, with the update, our IT folks did not let us know about the BlackMagic update. Probably a case of them not being users, so they aren't aware of the issue.
UPDATE: Installing BlackMagic Designs Desktop Video V10.4 did the trick. Playout to the external monitor for both PPro and AE is good to go. Many thanks, gents!
Glad you got it working.