Stopped video stream message straight after the stream is initialised
Hey
I have just set up a Victure PC530 camera with Homebridge and I can't get it to work. The stream is confirmed as working via VLC, however I tried different configs and the Home app just says No response while the log says this:

`[5/16/2021, 4:43:13 PM] [Camera FFmpeg] [Camera] Video stream requested: 1280 x 720, 30 fps, 299 kbps
[5/16/2021, 4:43:13 PM] [Camera FFmpeg] [Camera] Starting video stream: native x native, native fps, ??? kbps
[5/16/2021, 4:43:13 PM] [Camera FFmpeg] [Camera] Stream command: ffmpeg -i rtsp://admin:pass@ip/cam1/mpeg4 -an -sn -dn -codec:v copy -pix_fmt yuv420p -color_range mpeg -f rawvideo -payload_type 99 -ssrc 8690843 -f rtp -srtp_out_suite AES_CM_128_HMAC_SHA1_80 -srtp_out_params bffTyzX7hw+Jo+ICLUUzsqAssI+kvYuLXqLWOPvn srtp://anotherIP:60200?rtcpport=60200&pkt_size=1316 -loglevel level+verbose -progress pipe:1
[5/16/2021, 4:43:13 PM] [Camera FFmpeg] [Camera] Stopped video stream.`

The config is this:
```
{
            "name": "Camera FFmpeg",
            "cameras": [
                {
                    "name": "Camera",
                    "manufacturer": "Victure",
                    "model": "PC530",
                    "unbridge": true,
                    "videoConfig": {
                        "source": "-i rtsp://admin:pass@IP/cam1/mpeg4",
                        "maxStreams": 2,
                        "maxWidth": 1280,
                        "maxHeight": 720,
                        "vcodec": "copy",
                        "audio": false,
                        "debug": true
                    }
                }
            ],
            "platform": "Camera-ffmpeg"
        }
```