Finally got it. The bin was using the .dlls from Qt 5.6, but the .exe
was compiled with 5.7. It was some kind of timing error??
Just needed to redeploy using windeployqt.
Former-commit-id: 48c38ed9907000ed876e96acef804736aa134b81
Looks like TRFCNT is going haywire when the exe is run outside of the
IDE. The fact that it occasionally initialises close to 750 is
irrelevant.
Former-commit-id: e26f5396b90d2a1289ff1eeccafd76a04e779b20