Webpresenter latency on hdmi

Hello, i have a webpresenter for very little facebook live setup. Just for 2 camera and a audio mixer in usb to OBS. I use a general audio delay of 200 ms and is good when i use the SDI input but not the HDMI input.
I use 2 camera, one close and one larger. The camera for close up are in SDI on the web presenter,and the other on HDMI on the web presenter .
I have check my 2 camera, the camera with SDI and the camera with HDMI have no delay on the output. The problem is not the camera. With the same camera and my ATEM, the camera are sync.
But on the output (direct sdi or usb to obs) i have 2 frame delay on the HDMI input and no delay on the SDI input.
I have check the latency with this setup: A pixE5 player with a file with sync test. I output with SDI directly in the sdi port and with a converter to the HDMI port result 3 frame later for the HDMI input
The same test, HDMI output directly to HDMI web presenter input and a converter to sdi input and only 2 frame later for the HDMI input.
Ok, the converter delay from 1 frame but the web presenter delay 2 frames more on the HDMI input
How to have the same synchro ? It's a problem when you use it for this usage. Can you check this and maybe resolve it in the next firmware.

Here is a youtube link with the problem :

Thanks
And excuse my poor english

I get an audio delay using Web Presenter on Zoom. Using my computer's webcam I did not have any delay using Zoom, so if I'm not using OBS, is there any way to correct an audio delay in a third party service like Zoom, Skype, etc. if i want the advantages of WebPresenter and an external camera and microphone?

I have found I get better lip sync I turn off the camera input buffer.