As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON IFR CERTIFICATION UPGRADE OF APOLLO 2001GPS, C/W RFI TESTS. FOUND NAV COMM RADIO TO INDUCE EXCESSIVE RFI INTO GPS SYSTEM. CAUSE BEING NAV RADIO; OTHER NAV/COMM OF SAME TYPE OK IN EITHER NR 1 OR NR 2 SLOT. APPLICATION OF 'NOTCH' FILTERS HAD NO AFFECT ON SITUATION. RADIO SENT TO FACTORY FOR REPAIR.