You can also try flashing the hm-hoise.hex firmware under AVR Firmware to see the raw data coming in to see if it is noisy. I don't see the noise icons in your screenshot though so that seems unlikely. If the probe is non-isolated (you get continuity between the metallic braid and either of the pins on the mono connector), then make sure you're not grounding the wire through your smoker when it is closed in the lid/door.