Increase audio output
**Describe the bug**
2-way audio on iphone too quiet.

**To Reproduce**
Start and talk 2-way audio via iphone.

**Expected behavior**
I want to increase the volume on iphone in 2-way audio.

**Environment**
- Node.js Version: v16.14.2
- Homebridge Version: v1.4.0
- Camera UI Version: v5.0.16
- Operating System: Raspbian GNU/Linux Buster (10)

I increased audio output via filter in ffmpeg command.
-filter:a volume=volume=10.0
The recordings in Homekit Secure Video are loud and you can clearly hear the voices. But the 2-way communication is too quiet.
How can I increase the volume in 2-way communication?

           "name": "CameraUI",
            "port": 8081,
            "atHomeSwitch": false,
            "debug": true,
            "mqtt": {
                "active": true,
                "tls": false,
                "host": "192.168.178.64",
                "port": 1881
            },
            "http": {
                "active": false,
                "port": 7272,
                "localhttp": false
            },
            "smtp": {
                "active": false,
                "port": 2727,
                "space_replace": "+"
            },
            "ftp": {
                "active": false,
                "useFile": false,
                "port": 5050
            },
            "ssl": {
                "active": false
            },
            "options": {
                "videoProcessor": "/usr/local/lib/node_modules/homebridge-camera-ui/node_modules/ffmpeg-for-homebridge/ffmpeg"
            },
            "cameras": [
                {
                    "name": "Eingang_cameraui",
                    "manufacturer": "Foscam",
                    "model": "C1",
                    "motion": true,
                    "doorbell": true,
                    "motionTimeout": 0,
                    "unbridge": true,
                    "hsv": true,
                    "prebuffering": false,
                    "prebufferLength": 4,
                    "videoConfig": {
                        "source": "-fflags nobuffer -flags low_delay -fflags discardcorrupt -analyzeduration 0 -probesize 2000 -use_wallclock_as_timestamps 1 -i rtsp://192.168.178.183:8554/eingang -f alsa -ar 16000 -thread_queue_size 1024 -i default -filter:a volume=volume=10.0",
                        "subSource": "--fflags nobuffer -flags low_delay -fflags discardcorrupt -analyzeduration 0 -probesize 2000 -use_wallclock_as_timestamps 1 -i rtsp://192.168.178.183:8554/eingang -f alsa -ar 16000 -thread_queue_size 1024 -i default -filter:a volume=volume=10.0",
                        "stillImageSource": "-i http://192.168.178.35:88/cgi-bin/CGIProxy.fcgi?cmd=snapPicture2&usr=skunz&pwd=E4ooK5MH6qK3&",
                        "rtspTransport": "tcp",
                        "returnAudioTarget": "-f alsa plughw:CARD=P610,DEV=0 -ar 16000 -thread_queue_size 1024",
                        "maxStreams": 2,
                        "vcodec": "copy",
                        "acodec": "libfdk_aac",
                        "packetSize": 564,
                        "encoderOptions": "-preset ultrafast -tune zerolatency",
                        "mapvideo": "0:v",
                        "mapaudio": "1:a",
                        "audio": true,
                        "debug": true,
                        "debugReturn": true
                    },
                    "mqtt": {
                        "motionTopic": "home/cameraui/motion",
                        "motionMessage": "ON",
                        "motionResetTopic": "home/cameraui/motionreset",
                        "motionResetMessage": "OFF",
                        "doorbellTopic": "home/cameraui/doorbell",
                        "doorbellMessage": "ON"
                    },
                    "smtp": {
                        "email": "Eingang_cameraui"
                    },
                    "videoanalysis": {
                        "active": false
                    }
                },
                {
                    "name": "Garten Camera ui",
                    "manufacturer": "Reolink",
                    "model": "RLC-410W",
                    "motion": true,
                    "motionTimeout": 0,
                    "unbridge": true,
                    "hsv": true,
                    "prebuffering": false,
                    "prebufferLength": 4,
                    "videoConfig": {
                        "source": "-fflags nobuffer -flags low_delay -fflags discardcorrupt -analyzeduration 0 -probesize 2000 -i rtsp://192.168.178.183:8554/garten",
                        "subSource": "-fflags nobuffer -flags low_delay -fflags discardcorrupt -analyzeduration 0 -probesize 2000 -i rtsp://192.168.178.183:8554/garten",
                        "stillImageSource": "-i http://192.168.178.124/cgi-bin/api.cgi?cmd=Snap&channel=0&rs=wuuPhkmUCeI9WG7C&user=admin&password=U3dzjGCcvCF8",
                        "rtspTransport": "tcp",
                        "maxStreams": 2,
                        "maxWidth": 1280,
                        "maxHeight": 720,
                        "maxBitrate": 1024,
                        "vcodec": "copy",
                        "acodec": "libfdk_aac",
                        "packetSize": 188,
                        "audio": true,
                        "debug": true
                    },
                    "mqtt": {
                        "motionTopic": "home/camerauigarten/motion",
                        "motionMessage": "ON",
                        "motionResetTopic": "home/camerauigarten/motionreset",
                        "motionResetMessage": "OFF"
                    },
                    "smtp": {
                        "email": "Garten Camera ui"
                    },
                    "videoanalysis": {
                        "active": false
                    }
                }
            ],
            "platform": "CameraUI"