In addition, I can see on my Chrome...
Here is, actually I can't see any video on my Safari. I can listen mp3 file.
SampleVideo_1280x720_2mb.mp4
Yeni Kayıt 4-2.m4a
I'm using Safari on Mac (11.0.2, latest one)
I can see here on test website, on my board I can't see video (attached formats) and m4a audio record.
https://tools.woolyss.com/html5-audio-video-tester/