This is 4 year old advice that I’ve tried and it never makes a difference. I’ve used 5 different harddrive and thumbdrives, yet the slow loading/searching persists. 2.4 is the worst firmware to date with how long it takes to load and search for tracks.
I just uploaded these for proof. Because these things don’t seem to exist around here unless every single person has the same damn problem:
Slow load 1: Denon firmware 2.4 SLOW LOAD 1 - YouTube
Slow load 2: Denon firmware 2.4 Slow load 2 - YouTube
Slow load 3: Denon firmware 2.4 Slow load 3 - YouTube