Wwise internally run at a single sample rate, and if the source files are at different rates, it does real-time sample rate conversion to the internal rate. (all processing, mixing and effects are running at the same rate)
Please note the real-time sample rate is lower quality than the one you will find in the conversion settings, which is of very good quality.
In general, it is always preferable to:
- Have all your original assets at the same sample rate (usually 48000)
- Lower sample rate in Wwise if you wish your asset take less space (usually only for low frequency content), to a multiple of the internal rate
If you can't have all your originals to the same rate, use the conversion settings to make them to the same rate.