core: 0.91.0 - Camera stream recording getting stuck

Home Assistant release with the issue: 0.91.0

Last working Home Assistant release (if known): NA

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

Component/platform: https://www.home-assistant.io/components/stream/

Description of problem: From time to time the camera streaming would not start and complain that the steam is already recording.

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

  - platform: generic
    name: DaFang_stream
    username: !dafang_user
    password: !dafang_password
    authentication: basic
    still_image_url: https://192.168.86.50/cgi-bin/currentpic.cgi
    stream_source: rtsp://192.168.86.50:8554/unicast  
    verify_ssl: false
    scan_interval: 5    

Traceback (if applicable):

##Stream recording start (via script) 
2019-04-05 10:07:18 WARNING (SyncWorker_22) [homeassistant.components.python_script.record_camera_smart_noffmpeg.py] Start Recording {'entity_id': 'camera.dafang_stream', 'filename': '/tmp/video_20190405100718219019cameradafangstreamOutsideGarageMotion.mp4', 'duration': 20, 'lookback': 20}

##Another recording triggered, error returned:
2019-04-05 10:13:54 WARNING (SyncWorker_25) [homeassistant.components.python_script.record_camera_smart_noffmpeg.py] Start Recording {'entity_id': 'camera.dafang_stream', 'filename': '/tmp/video_20190405101354437809cameradafangstreamOutsideGarageMotion.mp4', 'duration': 20, 'lookback': 20}
2019-04-05 10:13:54 ERROR (MainThread) [homeassistant.core] Error executing service <ServiceCall camera.record (c:7b5adf2a7c664a598d92aa06a4ed916d): entity_id=['camera.dafang_stream'], filename=<homeassistant.helpers.template.Template object at 0x7f49607250f0>, duration=20, lookback=20>
Traceback (most recent call last):
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1147, in _safe_execute
    await self._execute_service(handler, service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1160, in _execute_service
    await handler.func(service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/entity_component.py", line 188, in handle_service
    self._platforms.values(), func, call, service_name
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/service.py", line 314, in entity_service_call
    future.result()  # pop exception if have
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/service.py", line 330, in _handle_service_platform_call
    await func(entity, data)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/camera/__init__.py", line 677, in async_handle_record_service
    blocking=True, context=call.context)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1138, in async_call
    self._execute_service(handler, service_call))
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1160, in _execute_service
    await handler.func(service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/stream/__init__.py", line 114, in async_record
    await async_handle_record_service(hass, call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/stream/__init__.py", line 217, in async_handle_record_service
    .format(recorder.video_path))
homeassistant.exceptions.HomeAssistantError: Stream already recording to /tmp/video_20190405100718219019cameradafangstreamOutsideGarageMotion.mp4!


##another one
2019-04-05 10:14:28 WARNING (SyncWorker_16) [homeassistant.components.python_script.record_camera_smart_noffmpeg.py] Start Recording {'entity_id': 'camera.dafang_stream', 'filename': '/tmp/video_20190405101428775627cameradafangstreamOutsideGarageMotion.mp4', 'duration': 20, 'lookback': 20}
2019-04-05 10:14:28 ERROR (MainThread) [homeassistant.core] Error executing service <ServiceCall camera.record (c:8d3e9ecdbb624c228075f1f73dbc1baf): entity_id=['camera.dafang_stream'], filename=<homeassistant.helpers.template.Template object at 0x7f48743e5240>, duration=20, lookback=20>
Traceback (most recent call last):
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1147, in _safe_execute
    await self._execute_service(handler, service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1160, in _execute_service
    await handler.func(service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/entity_component.py", line 188, in handle_service
    self._platforms.values(), func, call, service_name
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/service.py", line 314, in entity_service_call
    future.result()  # pop exception if have
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/service.py", line 330, in _handle_service_platform_call
    await func(entity, data)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/camera/__init__.py", line 677, in async_handle_record_service
    blocking=True, context=call.context)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1138, in async_call
    self._execute_service(handler, service_call))
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1160, in _execute_service
    await handler.func(service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/stream/__init__.py", line 114, in async_record
    await async_handle_record_service(hass, call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/stream/__init__.py", line 217, in async_handle_record_service
    .format(recorder.video_path))
homeassistant.exceptions.HomeAssistantError: Stream already recording to /tmp/video_20190405100718219019cameradafangstreamOutsideGarageMotion.mp4!

2019-04-05 10:17:26 WARNING (SyncWorker_21) [homeassistant.components.python_script.record_camera_smart_noffmpeg.py] Start Recording {'entity_id': 'camera.dafang_stream', 'filename': '/tmp/video_20190405101726592134cameradafangstreamOutsideGarageMotion.mp4', 'duration': 20, 'lookback': 20}
2019-04-05 10:17:26 WARNING (SyncWorker_21) [homeassistant.components.python_script.record_camera_smart_noffmpeg.py] Sleeping 60
2019-04-05 10:17:26 ERROR (MainThread) [homeassistant.core] Error executing service <ServiceCall camera.record (c:f3318128efe84cabbcb45d8104257676): entity_id=['camera.dafang_stream'], filename=<homeassistant.helpers.template.Template object at 0x7f4878782b70>, duration=20, lookback=20>
Traceback (most recent call last):
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1147, in _safe_execute
    await self._execute_service(handler, service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1160, in _execute_service
    await handler.func(service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/entity_component.py", line 188, in handle_service
    self._platforms.values(), func, call, service_name
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/service.py", line 314, in entity_service_call
    future.result()  # pop exception if have
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/helpers/service.py", line 330, in _handle_service_platform_call
    await func(entity, data)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/camera/__init__.py", line 677, in async_handle_record_service
    blocking=True, context=call.context)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1138, in async_call
    self._execute_service(handler, service_call))
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/core.py", line 1160, in _execute_service
    await handler.func(service_call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/stream/__init__.py", line 114, in async_record
    await async_handle_record_service(hass, call)
  File "/srv/homeassistant/lib/python3.6/site-packages/homeassistant/components/stream/__init__.py", line 217, in async_handle_record_service
    .format(recorder.video_path))
homeassistant.exceptions.HomeAssistantError: Stream already recording to /tmp/video_20190405100718219019cameradafangstreamOutsideGarageMotion.mp4!

Additional information: