homebridge-homematic: beta v1.3.0 // error: characteristic value NaN is not contained in valid values array!
Hey there, 
I am getting this error when trying to run v1.3.0-beta16 (also on the prior betas). 

**LOG:** 
```
Error: characteristic value NaN is not contained in valid values array!
at Characteristic.validateUserInput (/usr/local/lib/node_modules/homebridge/node_modules/hap-nodejs/src/lib/Characteristic.ts:1683:15)
at /usr/local/lib/node_modules/homebridge/node_modules/hap-nodejs/src/lib/Characteristic.ts:1155:24
at /usr/local/lib/node_modules/homebridge/node_modules/hap-nodejs/src/lib/util/once.ts:9:18
at /homebridge/node_modules/homebridge-homematic/ChannelServices/HomeMaticHomeKitContactService.js:229:11
at /homebridge/node_modules/homebridge-homematic/ChannelServices/HomeKitGenericService.js:473:13
at /homebridge/node_modules/homebridge-homematic/ChannelServices/HomeKitGenericService.js:685:13
at /homebridge/node_modules/homebridge-homematic/HomeMaticCCU.js:124:11
at /homebridge/node_modules/homebridge-homematic/HomeMaticRegaRequest.js:66:9
at IncomingMessage.<anonymous> (/homebridge/node_modules/homebridge-homematic/HomeMaticRegaRequest.js:42:9)
at IncomingMessage.emit (events.js:327:22)
```
Is that an error, which needs to be solved in **homebridge beta16** or in the node module **homebridge-homematic**? In v1.2.3 everything is working fine. 

Thanks! 
Jannis