So maybe a little less than a week ago, I've noticed the temperature on my hot side, more so under the hot hide has been fluctuating quite a bit.

I'm using a UTH and herpstat 1, which is set to 92 and a digital thermometer, with both probes under the substrate. The temperature on the glass never got above 95, and the temperature on top of the substrate was always 87-90 when I used my temp gun.

Recently though, the digital thermometer has almost always been reading 95+, and actually got to 98 today. It sometimes drops/rises a couple degrees in like a minute or 2, and whenever I check the digital thermometer, it's always 2-3 degrees different than the last I would check on it.

My BP also hasn't been in his hot hide for the last couple days, even after eating.

Basically, how can the digital thermometer be reaching 98 degrees when the herpstat is set to 92 and could something be not working properly if the temperature is changing this much?