So I have this problem too which is an absolute no-go for me (I am from the old generation that still listen to albums and not randomized playlists like young people tend to do these days).
And I am not going to edit thousands of tags so that titles will be improperly displayed with track numbers inside on all my devices either (and as I use FLAC, which takes space, I’m not going to duplicate everything).
I have legally (in France) three days left to return my player to the vendor. But if I could rest assured that this bug is actually going to be fixed in a firmware that I will be able to use (works for FLAC, update of the device can be done from a PC with Linux), I am willing to wait a little, the device being OK on other aspects.
Could a SanDisk official come here tell us if it is 100% sure that a fix is coming or if it is not yet so certain? Either way, it would be good to know.