WLM Plus Loudness Difference - Rendering to Master Bus

Hello fellow WLM Plus users.

I’m using the latest version (14.0) and I’ve noticed an interesting discrepancy that I’m trying to sort out. I presume it might be a user error, but I’ve yet to source the problem.

Let’s say I have a stereo file and I’ve inserted it into a session. The track is set to unity (0.0 dBs) and I pull up the WLM Plus Sound Meter to simply render the track in non-real time to determine its loudness. Great, 24 LUFS, I’m good. (See image two).

However! Let’s say I play that same track in real time through the master fader with WLM Plus as an insert. Both meters are set identically as far as I can tell. Both the stereo track and the master bus are set to unity (0.0 dBs). Somehow, at the end of the playback, WLM Plus shows it over two LUFS softer than the rendered version. (Image one) There’s nothing in the chain to mess with the gain. No other plug-ins to be seen. No additional settings on the meter. Shouldn’t be a difference, correct? One possible clue is the trim comes out different as well, but again, no gain adjustment to explain that discrepancy either.

Anyone else run into this issue and what might be the cause? It certainly messes with your head when mixing when one component of the mix isn’t set to loudness standards to begin with. Any ideas hive mind?