SD card formatting

I have a 128gb SD card (SanDisk Ultra) which I formatted for a Hiby R3 Pro Saber (DAP).  I chose exFat with a 128K Allocation Unit Size. My music files are Mp3 and FLAC. Is 128K (and exFat) the preferred configuration, or should I re-format to another?  What would offer the best (musical?) performance?  I just joined this website, so my apologies if I chose the incorrect discussion-group.  Thank you for your time.