Playing RTP stream on Android 4.1.2 (Jelly Bean)

I'll try to keep it quick. Using FFMPEG I started a stream on my PC. Here is the code:

import subprocess

def start_stream():
 command = [
 'ffmpeg',
 '-f', 'gdigrab', # Desktop capture (Windows)
 '-framerate', '15', # Low framerate for higher performance
 '-i', 'desktop', # Capture desktop
 '-c:v', 'libx264', # Video codec (H.264)
 '-preset', 'ultrafast', # Ultra-fast encoding preset for minimal latency
 '-tune', 'zerolatency', # Zero latency for real-time streaming
 '-x264opts', 'keyint=15:min-keyint=15:no-scenecut', # Frequent keyframes
 '-b:v', '500k', # Low bitrate to minimize data usage and reduce latency
 '-s', '800x480', # Resolution fits phone screen and helps performance
 '-max_delay', '0', # No buffering, instant frame output
 '-flush_packets', '1', # Flush packets immediately after encoding
 '-f', 'rtp', # Use mpegts as the container for RTP stream
 'rtp://192.168.72.26:1234', # Stream over UDP to localhost on port 1234
 '-sdp_file', 'stream.sdp' # Create SDP file
 ]
 
 try:
 print("Starting stream...")
 subprocess.run(command, check=True)
 except subprocess.CalledProcessError as e:
 print(f"Error occurred: {e}")
 except KeyboardInterrupt:
 print("\nStream interrupted")

if __name__ == "__main__":
 print("Starting screen capture...")
 start_stream()

Now, when I start the stream I can connect to it in VLC when I open up the stream.sdp file. Using the same method I can open up the stream on my iPhone, but when I try to open it on my old Android phone the stream connects but the screen is black. However, when I turn the screen I can see the first frame that was sent to the phone. Why does the stream not work?

I will be thankful for any and all advice :)