Picture of the track is not displayed correctly

Hi
Sometimes I have such trouble ! The cover of the track is not displayed.

I cast by using Bubbleupnp and Mconnect. At the beginning, pictures were displayed correctly. Since yesterday here is what I have!
It appears on Chrome/Windows or Anfroid Myvolumio apps.

When i listen music I have in the local library (on the sd cad of the the RPI), picture is ok.

Have I cache to clear ? A log file to read ?

Thanks for helping

Georges