I’ve noticed some sound issues in the Airbus A340 on SU4. The flap sounds do not play at all—I can’t hear them in the A340. I’ve seen similar issues in the A350, where sometimes the sounds are missing in flight. All aircraft versions are up to date. I don’t know if it’s different in SU3 can only speak from my own experience.
Additionally, during the Engine or APU fire test, the sound is audible, but it’s not as loud as in real life. Other sounds seem correctly balanced, but this one is noticeably quieter.