X-Plane 11 uses the FMOD commercial sound engine. By design, FMOD does not allow duplicate sound banks. X-Plane 11.33 handles most cases of exact duplicates gracefully. However, there is still one edge case where a duplicate sound bank can cause a crash.
If you see an FMOD crash in X-Plane 11.33 or later, it is most likely due to an outdated third party aircraft sound bank that conflicts with a default aircraft sound bank. These two aircraft cannot be used at the same time. The most likely place to find the duplicates is in the AI aircraft window. In addition, the third party aircraft author should be informed of the crash so they can update their aircraft’s sound banks.