We used to have debug settings for audio rolloff (how far sound travels) and doppler effect strength (how much pitch changes based on relative motion), but somewhere those were lost. They were both very useful in SL motorsports, as we race around large, full sim builds, and I used to adjust them often at race tracks, but that ability is only available now on Singularity, which is getting pretty dated now. The default setting is fine for most cases, but there are plenty of cases where I'd want it lower or higher - lower in a crowded residential sim, higher in a full sim sports environment.