Severe datamoshing

[arduino-man]

When running the following code on a Raspberry Pi 4 with the CSI camera module 3, the saved file contains severe datamoshing.
Is there a known way to mitigate?

defmodule Rpicam.Pipeline do
  use Membrane.Pipeline
  
  @impl true
  def handle_init(_ctx, _opts) do
    spec =   
      child(:source, %Membrane.Rpicam.Source{
        camera_open_delay: 1000,
        framerate: {50, 1},
        width: 1920, 
        height: 1080, 
        timeout: 30000})
      |> child(:sink, %Membrane.File.Sink{location: "/data/output.h264"})

    {[spec: spec], %{}}
  end

  @impl true
  def handle_element_end_of_stream(:sink, _pad, _ctx, state) do
    {[terminate: :normal], state}
  end

  @impl true
  def handle_element_end_of_stream(_child, _pad, _ctx, state) do
    {[], state}
  end
end

# Start and monitor the pipeline
{:ok, _supervisor_pid, pipeline_pid} = Membrane.Pipeline.start_link(Rpicam.Pipeline)
ref = Process.monitor(pipeline_pid)

# Wait for the pipeline to finish
receive do
  {:DOWN, ^ref, :process, _pipeline_pid, _reason} ->
    :ok
end