HomePod Minis reporting different temperatures.

I have two HomePods minis that are reporting 3°C difference.

I have put these next to each other, not played music through them for over a day, let them 'calibrate' (i.e. left them powered for hours without use) and even changed the power supply (both between them and a different adapter) but the difference is a constant 3°C no matter what the external temperature is.

Humidity is 1% difference at most and often the same value.

The highest temperature one is a MY5G2B/A model running v26.2 (23K54) software

The lowest temperature one is a MTJ3B/A model running v26.2 (23K54) software

Having worked in IT within the temperature controlled logistics business for 30+ years I do know a little about temperature monitoring (and way too much about calibration and thermal mass of sensors) and know this is not great or something environmental that is local to the device.

Is there anyway I can put a 'fiddle factor' into these so I get a consistent reading when I put them into different rooms and to stop Siri answering with "It's ranging from 16°C to 19°C"?