Vintage models struggling with modern MP3 formats

Hi everyone o/

I was thinking of getting a new EDC dumbphone since my SE w610i crashes pretty frequently when trying to play certain mp3 files. I’ve done a bit of digging and it seems that older models can struggle with more up-to-date mp3 formats, causing crashes. This explaination sounds likely, as even my old iPod nano 4g would completely give up with certain specific songs.

Does anyone know of any relatively vintage model dumbphones that don’t have this issue? Additionally (and I appreciate this might be outside of this forum’s specialities) does anyone know how I might be able to change my mp3s into older formats that my phone might be able to handle?
Failing all of that, I am very open to reccomendations for modern dumbphones that have good mp3 player software/hardware. Beyond basic text + calling, music takes priority for me.

Nice to be back on the forum again anyhow :¬)