Weatherhat rain/humidity sensors issues

So I’ve had my solar-powered WeatherHat weather station running for a few months now and it’s generally great, but there are two things not working properly.

  1. The humidity sensor on the WeatherHat reports about 2-3x what my other enviroPi’s do, for example 21% vs 53%. Is there a way to calibrate it? This happened even when the different devices were next to each other, so I don’t think it’s a factor of it being in my garden shed (and in the UK anyway).

  2. The rain sensor is not sensing any rain in its little tray, even when it’s definitely raining outside.
    The tray is level according to the in-built spirit level bubble, and I’ve tried reseating the RJ11 plug.
    Can I make it work and will I need to take the thing apart? Whereas the wind sensor definitely senses the wind.