Bonus question: Mine shows three...
CAL_MAG_PRIME is 73225 which appears to be the external one (Hobbyking M8N GPS) and that's good.
But why are there two "internal" ones? And why do these have the same IDs that marimach77 is also seeing? @marimach77: Have you tried rotating the external compass only, to see whether it is indeed being picked up?
I am running QGC and PX4 Master on a Pixracer, both downloaded yesterday (but had the three Compasses already with a build from last weekend).