Source:
MSX Forum
Jos van den Biggelaar and Dennis Koller (a.k.a.
Yobi and
DD in our forum, respectively) are currently working in a hardware MP3 player for MSX. They already have a
functional PCB prototype that fits into a Konami-sized MSX cartridge case. According to the information published by Jos in
this forum thread, the cartridge uses an ATMEL CPU (20 MHz) for the communication with the VS1011 MP3 decoder and a Philips I2C interface to control the Bass/High/Volume levels. It can handle transfer rates up to 320 Kbps. If you are interested in this cool device you should better let Jos know this, the more orders the cheaper it will be.
Relevant link:
MP3 cartridge for MSX (forum thread)