iXpand app - poor MP3 quality

I have had an iXpand 64Gb for several weeks now and I believe it has at least as many negatives as positives.
The one thing that really stands out negatively is the poor MP3 decoding by the iXpand media player. My MP3s (Lame V0) sound as if they are <128Kbps when played through the built in media player but when I play the same files with the iPhone mediaplayer or a streaming app like Evermusic they sound terrific.
Fortunately the iXpand media player also plays FLAC and these files sound fine. It’s just very frustrating that I have to sacrifice so much space in order to enjoy my music.
Is the poor handling of MP3s something that can be improved in an update of the app?