Homebridge not listening on port 1883
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**Describe Your Problem:**
I am running the MQTTthing plugin. None of my MQTT devices can access it through port 1883 (default port). I did not have this issue when I was running Homebridge on a typical Raspbian image. This issue is specific to the Homebridge-Raspbian image.

I ran netstat -lptn through the terminal and port 1883 is not listening. Is there something I'm missing? Should this be posted on the MQTTthing plugin page instead?  

**Logs:**

```
_log from my device attempting to connect via MQTT_
00:53:39 UPP: Multicast (re)joined
00:53:49 MQT: Attempting connection...
00:53:49 MQT: Connect failed to 10.0.1.23:1883, rc -2. Retry in 10 sec
00:53:50 UPP: Multicast (re)joined
00:54:00 MQT: Attempting connection...
00:54:00 MQT: Connect failed to 10.0.1.23:1883, rc -2. Retry in 10 sec
00:54:01 UPP: Multicast (re)joined

_
```


**Environment:**

* **Homebridge Raspberry Pi Image Version**: 1.0.17
* **Node.js Version**: v14.15.3
* **NPM Version**: v14.15.3
* **Homebridge Version**: 1.1.7
* **Homebridge Config UI X Plugin Version**: 4.36.0


