track notification from Olimex MOD-MP3 in standalone mode

I am using an Arduino to drive the switch of an Olimex MOD-MP3 player in standalone mode by grounding MOSI, DCS, and SW-CS1 pins on the UEXT connector.

Being pretty much a total noob with this stuff, I don’t know what is possible with this module. I would like for Arduino to be notified when the track finishes playing. Can anyone give me a clue on where to start figuring out how to do this?

I had thought by some data might be gleaned by watching the MISO pin, but the output from the MOD-MP3 never goes high on that pin…