Temperature Protection KB resistance not working properly

[Uun]

On my Fire/Fire tank the KB resistance from Temperature Protection is very inconsistent (I tracked this on my Combat Monitor). There is no resistance (100% distance) without a target in range. There were numerous instances of the resistance failing to appear when I entered combat or dropping back to 100% distance after a few seconds while I was still in combat. I don't think I ever managed to get more than 20s uptime. It also appears to be stacking per target, as it was showing 1% distance (not 50% distance) when it was working.