Safari, WKWebView video slow loading issue

my web service has video content. the problem is in chrome browser, downloading and playing video is much faster than Webkit browser (Safari and WkWebView).

we are struggling to find the reason why there is huge gap between two browsers.

we've checked browser inspector and there's something look like error in safari inspector that doesn't appear in chrome.

There are two cases in network section.

First red header case that I think something went wrong

Second yellow header csae that I think succeeded to donwload

Safari, WKWebView video slow loading issue
 
 
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