A few years ago, Dynon announced a modification that needs to be done to the D-10A's compass. Today I accomplished the mod. It's pretty simple and straightforward. The procedure has you take off the cover the compass module, locate D3, a tiny surface-mounted diode, and carefully clip it off the circuit board. This mod was needed to correct an issue with the accuracy of some of their Outside Air Temperature (OAT) probes. [Superseded.]