hi there, i don't know if this will help, to be honest i didn't watch the video but i was having issue with robot voice.
In my case that was when i was streaming and using Audacity in the same time and use audacity than OBS for the voice, the gain, noise gate etc.
I was having this issue only in some Game who need more CPU or Core and solve it just by going in the "Windows Task Manager" (ctrl+Alt+Suppr). Then find your voice/microphone tool if you have one or OBS in the "processus Tab", you can right click on the program in "application" tab too and click on "go in the processus tab"
Finaly, right click on the processus -> priority -> Above normal / High.
For me, i always set my Game "High" when Heavy CPU demanding, OBS and Audacity "Above normal" and that it, this solve my issue.
An other possibility can be because all of your device didn't have the same profile, like a microphone setup in 41MHz but OBS sound in 48Mhz etc. The other important thing is the bits (16/24/ etc) and the quality (DvD / Studio)
For me i use microphone 2 channel (for the mic), 16bits 48000 Hz (48Mhz) in DvD quality everywhere.
OBS seems to like when everything as the same profile, and this as solve issue in some Games who try to change my device setup (like many ubisoft Game: The Division / Ghost Recon Wildlands etc)
Not sure if all of this will help you, i hope yes and sorry for my english :/
