Historic Values: multiple errors in temperature 
Hi. When accessing historic data via HomeKit (for example with the eve app) I'm having the problem with multiple thermostats (3x HmIP-eTRV-2, 2x HmIP-WTH-2) that numerous invalid temperature readings of always 0.0°C are reported. This happens 1-2 times of 180 measured values a day with one of the WTH-2, up to every other value of a single eTRV-2 being invalid... till hardly any usable value with an other eTRV-2; only one or two usable values a day. Even a single erroneous 0.0 messes up the graphs. The devices are all reachable and this never occurs when displaying the current data via homekit or hmip nor with thermostats of other standards. Only when accessing the historical data. I've seen this for at least a year with currently homebridge 1.2.5 on TrueNAS Core jail; every other aspects of homebridge and homebridge-homematic are working exceptionally fine. 

But any idea what could be the problem when accessing historical data? Thank you!
