

I’d suggest looking at small embedded computers and hats for them to fit your objective.
Since you’re familiar with Linux, I’m thinking an Arduino might work out. There’s probably a better way but I’m imagining you configuring it to work like a USB drive and dropping in playlist files along with your music and using the hat to select your preferred playlist like a homemade iPod.
You’ll want to avoid the generic junk mp3 players online since there’s no way to be certain it’s free of radio chips before detailed inspections. Since that stuff is typically pumped out with whatever junk was available that day.
Would 256GB/s be too slow for large llms?