To get my Raspberry Pi 4 and Volumio up and running ASAP I used as the source a small 8GB USB stick with just a few albums on - and everything works perfectly !
So as my music library is only 27GB at present I put them on a 32GB USB stick but unfortunatly will will not update the music database - it just spins round and round ( for hours!). I have now tried 2 sticks a Sandisk and a Lexar - both 32GB to no avail. As soon as I put in a sn 8Gb stick it re-reads the database quite quickly. All sticks are FAT32 and can be read on my Linux desktop with no problems.
Any suggestions? ( I don’thave a NAS )
Thank you
Hi UncleOilybag, welcome to Volumio, and the Community. 
FAT32 should be ok up to 32GB. But perhaps you are pushing this too far. Can you add say 20GB of your music library, and see how that goes. If that fails then can you reboot, set a library rescan going (for 30 mins or so), and then post the link to system logs here please?
Would you share some system logs please?
Thank you for your assistance. I reduced the files so that about 75% of USB stick was full and this seemed to work OK.
Is is possible just to use 2 x 32GB USBs in 2 of the USB slots on the Raspberry Pi which are say half full - would Volumio scan both USB sticks?
Why you don’t use bigger one ?? I play from 512GB USB stick and works.