Problems with HDMI passthrough via Framemeister and LGP

[Yabe_uke]

So I got the Framemeister some months ago and everything's fine and dandy except one thing: HDMI passthrough. It seems to work flawlessly, and I use it all the time to play, as my TV only has 2 HDMI inputs, so I can hook up one more system to the setup, but if I want to capture thing go nuts. I usually have the Framemeister connected to an AverMedia Live Gamer Portable, and used it to capture some retro gaming footage, but if I try to capture the HDMI passthrough signals it goes out of range and it's unable to capture. This happens with all my HD systems: PS3, PS4, PSTV, WiiU and OUYA. If I try to capture them directly hooked up to the LGP it works no problem. I can always deactivate HDMI direct, but 20 extra ms seems no good to me (even though I'm no speedrunner). Anyone knows the solution/why this happens? I can cope with the extra lag if there is no other way, but at least I would like to know the cause of this mess. I leave a video link with the symptoms so you guys can diagnose correctly. Thanks everyone in advance!
https://youtu.be/odjL-n44mbg