Inaccurate temperature readings on IBBQ-4BW

Is there a way to calibrate the 4 temperature probes on an IBBQ-4BW? I recently smoked 3 tri-tips simultaneously and noticed a significant difference in the temp readings between each on my new IBBQ-4BW. I tested the 4 probes in ice water and boiling water, see my results below.

The temperature readings can be calibrated via the INKBIRD app.

Please put the probe and probe’s cable (excluding the probe’s plug) in a 150C (302 F) oven for 30 minutes, then test it with boiling water ( please hang the probes and do not let them touch the container). Can it work?

Please note that the cable of the probe (silver wire) is not waterproof. Please do not immerse the cable into the water when washing the temperature probe.
Otherwise, it will show an incorrect temperature if there is water in the cable.
Please do not put the probe/the probe’s cable in the fire or place it at which temperature higher than 250C/482F. Otherwise, the probe and the cable will be damaged.

Thank you for the feedback. Please let me know if the type of thermocouple used in your probes i.e. Type “J”, Type “K” or Type …

It is NTC type.