You may try Avdshare VideoGo to increase the Sound volume of a video or audio file
Working as an Audio Volume Booster, Avdshare VideoGo
can easily boost sound volume for almost all kinds of audio file like
increase MP3 volume, increase WAV volume, increase FLAC volume,
increase AAC volume, increase AC3 volume, M4A, WMA, AU, DTS, AIFF,
OGG, MP2, APE, OPUS, CAF, VOC, etc.
