As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATTEMPTED TO USE SATCOM, ATTEMPTED ON BOTH SAT 1 AND SAT 2. WE COULD HEAR CALL BUT THEY COULD NOT HEAR OUR TRANSMISSIONS. 2 ATTEMPTS WITH MED LINK AND 1 ATTEMPT WITH DISPATCH ON NR 1 & 2 STATCOM. ACFT GROUNDED. ACCOMPLISHED SYS OPS CHECK REF AMM 23-15-00. SYSTEM OPS CHECKS NORMAL.