Cameras not stable after update
**Describe The Bug:**
It's been a while since I updated the plugin. Maybe 2-3 months.
Anyway, I have updated the plugin but it seems 3 of my cameras are not stable.
After restarting homebridge I can view the livestream but if I close and try to open the live stream again, it loses the connection.

I checked the changelog and it seems now we have built-in ffmpeg. 
I added 
"videoProcessor": "ffmpeg",
to get back to my old setup but it is no good.
Additionally, after update connecting to my cams seems to be slower than before.

**To Reproduce:**
Restart homebridge,
go to homescreen and open up a camera livestream
close the livestream
try to open it again.

**Expected behavior:**
Livestream should open again.

**Logs:**


```
[FFMPEG] ffmpeg exited with code: null and signal: SIGKILL (FFMPEG Stream stopped!)
```
I am getting above log occasionally. Sometimes there is no log output at all.

**Homebridge Config:**

```json
 "platforms": [
        {
            "videoProcessor": "ffmpeg",
            "cameras": [
                {
                    "name": "cam1",
                    "manufacturer": "DAHUA",
                    "model": "IPC-HFW81200E-Z",
                    "serialNumber": "1L047ACPAW00037",
                    "firmwareRevision": "2.400.0000.7.R, build : 2015-09-13",
                    "videoConfig": {
                        "source": "-rtsp_transport tcp -vcodec h264_mmal -re -i rtsp://user:pass@camip",
                        "maxStreams": 2,
                        "maxFPS": 25,
                        "maxBitrate": 2816,
                        "vcodec": "libx264",
                        "audio": true,
                        "debug": false
                    }
                },
                {
                    "name": "cam2",
                    "manufacturer": "DAHUA",
                    "model": "IPC-HFW1320S",
                    "serialNumber": "3K058D5PAG00056",
                    "firmwareRevision": "2.620.0000002.0.R, Build Date: 2017-08-30",
                    "videoConfig": {
                        "source": "-rtsp_transport tcp -vcodec h264_mmal -re -i rtsp://user:pass@camip",
                        "maxStreams": 2,
                        "maxFPS": 20,
                        "maxBitrate": 3584,
                        "vcodec": "libx264",
                        "audio": false,
                        "debug": false
                    }
                },
                {
                    "name": "cam3",
                    "manufacturer": "ProLook",
                    "model": "PR-F1330IP-BL",
                    "serialNumber": "C5J143930266",
                    "firmwareRevision": "3518C_IMX225_W_6.1.23.2",
                    "videoConfig": {
                        "source": "-rtsp_transport tcp -re -i rtsp://user:pass@camip",
                        "maxStreams": 2,
                        "maxFPS": 25,
                        "maxBitrate": 1024,
                        "vcodec": "libx264",
                        "audio": false,
                        "debug": false
                    }
                }
            ],
            "platform": "Camera-ffmpeg"
```

**Screenshots:**

**Environment:**

* **Node.js Version**: v14.5.0
* **NPM Version**: 6.14.5
* **Homebridge Version**: 1.1.1
* **Homebridge Camera FFmpeg Version**: 2.2.2
* **Homebridge Config UI X Plugin Version**: 4.23.2
* **Operating System**: Raspian


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