rotorhead8, yes, the school owner could be correct, when you buy a Bose X you have a choice of two different microphones. The high impedance one is compatible with all R22s and most civilian helicopters. The low impedance one is used in military aircraft and some civilian versions of military helicopters.
Take the foam cover off the mic and have a look at the shape. The high impedance (electret) mic has a rounded, flattened shape, while the low impedance (dynamic) version is shaped like a light bulb.
If that is the problem then the solution is to purchase a high impedance microphone and replace the microphone, it's quite a straightforward operation. Or even better, take it back to where you bought it and ask for the correct mic!