There are two primary reasons for this:

• Using a grounded thermocouple
• Static particles in the Data Bridge electronics

If you are getting spikes in temperature when a laptop is plugged in versus running off its battery, this is a ground loop and is the reason why we require ungrounded thermocouples.

If you are seeing big spkes up and down during a roast, charged particles (chaff) are almost certainly the culprit.  To remedy this:

1. Unplug both the USB cable and TC connector(s) from the Data Bridge.
2. Using compressed air or some very strong breaths, try to blow out any particle building from inside the case
3. If #2 doesn't work, open the plastic enclosure and blow off the circuitry more directly.