core: Generic Camera stops working after several seconds (rtsp)

The problem

After i upgraded from 2021-04 to 2021-05-4 and -5 in lovelace the camera stream stops working after some seconds. In lovelace i have four streams showing the mjpeg debug stream from frigate and in parallel the same cameras directly attached to the generic plugin. When I open the lovelace tab everything seems to be normal. The delay of the generic camera stream is normal compared to the old version. After 2-3 sec. the stream stops for a short time and then you can see a more current stream much closer to the current time (and thats pretty cool). But again after some seconds, the cameras stop streaming one by one. If I click on the camera picture, then the same happens (here the stream window turns into grey). I tried several browser, but the behavior is the same. (lovelace set to auto and preload activated) Today i tried the 2021.6.0.dev20210523, but here its the same!

In the standard logs you do not find anything.

What is version of Home Assistant Core has the issue?

2021.6.0.dev20210523

What was the last working version of Home Assistant Core?

2021.4

What type of installation are you running?

Home Assistant Container

Integration causing the issue

generic

Link to integration documentation on our website

https://www.home-assistant.io/integrations/generic

Example YAML snippet

- platform: generic
  name: Cam1g
  still_image_url: http://camera1/snap.jpg?JpegCam=0
  stream_source: rtsp://user:password@camera1:80/1
  username: user
  password: password
  framerate: 20

Anything in the logs that might be useful for us?

n/a

Additional information

No response