Always looking for improvements, Seeed has replaced the version 1-based WT5001 chipset MP3 player with the KT403A, making a much smaller and still very capable serial-communications based MP3 player.

Features:

• Grove-compatible Interface
• Micro-SD slot (32GB maximum)
• 3.5mm audio jack
• Status indicator LED
• 10 EQ presets

Specifications:

• 9600 bps 8/n/n standard asynchronous serial communication
• Support sample rate of 8/11.025/12/16/22.05/24/32/44.1/48(KHz)
• MP3, WAV, WMA file formats
• 24-bit DAC output, 90 dB (at Max.) dynamic output range, signal-noise ratio at 85 dB
• FAT16; FAT32 files system support
• 5VDC input
• Onboard 3.3V LDO regulator (100mA capable)
• 15mA standby current draw
• >40mA operating current draw
• -40 to +80°C operating temperature range

Links:

• Serial MP3 V2 Player wiki
• Github – Library