Unfortunately, even in 48kHz format, you get a distorted file. The upper frequencies in 48kHz format are cut less than if you add a file in the 44.1kHz format. But then lower frequencies are beginning to be reduced. For mobile small projects, this is probably not essential. But for serious projects - this is unacceptable.
To reproduce - just add whiteNoise wav file in different formats to UE and check how it sounds with any Freq Analyser.