Nginx Reverse Proxy serving MP4/MKV Stuttering

I'm using Nginx as a reverse proxy to serve HTTP video streams over HTTPS to avoid mixed content issues. However, I'm experiencing stuttering during video playback.

Problem:

The videos start playing but frequently pause at the same exact time during playback. Every time I try to watch a video, the stuttering happens at the exact same second.This issue occurs with both MP4 and MKV files.

The stuttering does not occur when accessing the videos directly from the backend server; it only happens when accessed through the Nginx reverse proxy.The stuttering does not occur when working with m3u8 files.

Here is my reverse proxy code:

server {    gzip_static off;    resolver 1.1.1.1;    listen 25443 ssl;    server_name my.proxy;    ssl_certificate /etc/letsencrypt/live/my.proxy/fullchain.pem;    ssl_certificate_key /etc/letsencrypt/live/my.proxy/privkey.pem;    ssl_protocols TLSv1.2 TLSv1.3;    ssl_ciphers HIGH:!aNULL:!MD5;    ssl_prefer_server_ciphers on;    location /proxy/ {        rewrite ^/proxy/(.*)$ /$1 break;        proxy_pass http://example/$1;        proxy_set_header User-Agent "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0";        proxy_set_header Referer "example";        proxy_set_header Host example;        proxy_set_header X-Real-IP $remote_addr;        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;        proxy_set_header X-Forwarded-Proto https;        proxy_intercept_errors on;         error_page 301 302 = @handle_redirect;    }    location @handle_redirect {        add_header X-Debug-Redirect-URL $upstream_http_location;        set $new_url $upstream_http_location;        if ($new_url = "") {            return 500;        }        add_header X-Debug-New-URL $new_url;        proxy_pass $new_url;        proxy_set_header User-Agent "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0";        proxy_set_header X-Real-IP $remote_addr;        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;        proxy_set_header X-Forwarded-Proto https;        proxy_set_header Accept-Encoding "";    }}

Do you guys know any ways I could Optimize this nginx configuration ?

Any ways to prevent stuttering in my videos ?

What I tried:

Disabled gzip compression by setting gzip_static off;.

Adjusted buffer sizes in Nginx:Tweaked proxy_buffer_size, proxy_buffers, and proxy_busy_buffers_size.

Checked network latency:Latency between the client and server is minimal.