Arylic S50 Pro+ USB

Hello,

I bought an Arylic S50 Pro + and after I connected it I tried USB stick and the USB memory is no longer visible when the player is turned off and on again.

But when I pull it out (USB memory stick) and plug it in again, the device sees it. And every time I turn player on, the same problem occurs.

Question: Is it a design feature that needs to be done every time or a software bug?

Thanks for the help in advance