Hey @ca61ino 

If you can select/activate Hifi, you should hear Hifi. Do your audio settings look like mine? I have iOS, but it should look similar on Android.

Do you have a few examples that are only played as mp3?

Hi thanks, yes it's all the same as you...

Hi @ca61ino, how did you find out you don't have HiFi?

@ca61ino 

Do you mean maybe your own uploaded music?

@ca61ino our devs are aware of this problem. It is a display issue only as the song will play in HiFi even when you don’t see the HiFi logo in the album cover.
If your problem is different than this, please let us know.
Apologies for the inconvenience

So thanks to all people for your answers. Nothing to do, if l stream with Wiim pro+ it appears the logo Flac, with Marantz 7000 streaming amplifier mp3 320 kbps.