Hi,
I have troubles importing .wavs to ue4 that were exported from ableton live. They’re 16bit @ 44.1kHz, but won’t load if I drag them into the content browser. However, if I re-render those files with audacity to the exact same format (16bit, 44.1kHz) they’ll work. What could that be?
Hmm strange, change the name of the wav file to something simple like “test” and then try it again. What exactly happens when you import them? (error message, crash,…) 
/shot_in_dark
Have you compared any file differences via explorer? File size or something else? If the file size is different, open them up in a text editor and see if you can spot anything. Maybe the DAW is saving some additional information to the end of the file that UE doesn’t want?
Can you check your output log for the specific error message? My suspicion is that ableton is exporting to one of the many wav formats we don’t support importing at this time (you can see all the variations by looking at the WAVE_FORMAT_… defines in ://www-mmsp.ece.mcgill.ca/documents/AudioFormats/WAVE/Docs/MMREG.H). Of those we currently only support WAVE_FORMAT_PCM, WAVE_FORMAT_ADPCM, and WAVE_FORMAT_DVI_ADPCM.