Is this a problem ? I'm using a dna 200 with uwell crown 3 .5 coil. In tc mode I've locked resistance and the resistance still fluctates +/- .1-.2 ohms. It does the same in tc mode without the ohms locked. It does the same in regular power mode/non tc. Is this normal and should the display show the ohms fluctuate while the resistance is locked and in tc mode ?