I have a -30dB loss in one ear at 500Hz
It hasn't affected my controlling but was a fail on the NATS assessment, but isn't on the CAA regulations to hold a medical.
Before I joined I got my own Class 1 (just to be sure) but when I spoke to OHS at NATS they were fairly relaxed and pointed out 500Hz is outside the range of a regular human voice
As for the APP, the cube matrix look exactly like the one NATS gave us (back in 2008)