core: Cant stream generic camera "Header Missing"

Home Assistant release with the issue:

0.90.2

Last working Home Assistant release (if known): NA

Operating environment (Hass.io/Docker/Windows/etc.): Docker on Ubuntu

Component/platform: Stream Component with Generic camera component

Description of problem: When I call the code below, I expect the stream to start playing on my living room chromecast. The chromecast just buffers, and I get a “header missing” error in the logs.

{
  "entity_id": "camera.my_camera",
  "media_player": "media_player.living_room"
}

my_camera is a wyzecam 2 running dafang hacks.

Problem-relevant configuration.yaml entries and (fill out even if it seems unimportant):

camera:
  - platform: generic
    still_image_url: https://dafang/cgi-bin/currentpic.cgi
    username: !secret cam_username
    password: !secret cam_pw
    stream_source: rtsp://dafang:8554/unicast
    verify_ssl: false
    name: my_camera
    framerate: 25

stream:

Traceback (if applicable):

Header missing
4:49 PM components/stream/worker.py (ERROR)

Additional information: