Is it every video, or just this one…? If there’s another one, smaller, that you can post up somewhere for others to download and try on their systems, might give you a clue…
Win10 or Win7…?
FWIW - I’ve had no similar concern with videos I’ve had playing back in Cubase (converted to H.264 MOV container format first, using AudioSpot MediaER Toolkit Audio Spot - Convert Video, Replace Audio in Video, Converter | audio spot ). But they’ve generally been under 5mins duration - not that that should make any difference.
Good luck.!
Bob
(PS:- there is another tool, a video-player VST plugin that might help; you can download a free demo here VidPlayVST.com - Home )