By default, resamplers apply normalization. This means that the volume of every individual note is increased to the same volume. However, this isn't necessarily what you want, because different vowels will naturally be pronounced at different volumes. The most common issue is that the i vowel should be quieter, but normalization makes it too loud. You can lower the amount of normalization overall using the P flag. Go to Project > Project Property, and in the Rendering Options box, input a lower value for P like P20. (The default amount is P86.)