Df miniplayer used along with Nano, corrupting micro SD card.
it runs, when battery is fully charged. after 8~10 times of charging cycle, suddenly one day it stops playing songs from DF Player.
when checked, the memory card is corrupted and it gives only option to format, which is also unsuccessful. this happened 3 times to me.
You can use a dedicated regulated 5V power source instead of drawing from the Nano.
Try the card on a PC to see if the card is bad or you have a power issue.
Does the issue persist after a full format and re-recording of the mSD? All wiring reliable? Plays on PC as suggested by
@sonofcy ?
First guess would be power supply fault, but please show your code and either a clear photo or schematic.