There is a digital circuit part in the memory card. The digital circuit part first reads the data in the card and converts it into an audio signal, then sends it to the amplification part of the analog circuit, and finally broadcasts the sound through the speaker.
So when the digital circuit goes wrong, the card can't play songs.
Use the computer to check if there is anything wrong with the card. Is there any song in Cary? And will the card not be installed?