I'm using female pin headers on top of the audio shield, and male pin header under the teensy board. So I don't need to solder them together. The only problem of this setup is that it's not breadboard friendly. But for permanent use, I think it's reliable and stable.
#define SDCARD_CS_PIN 10
#define SDCARD_MOSI_PIN 11
#define SDCARD_SCK_PIN 13
This should work. I recently bought the 4.1 and the rev D audio adaptor. By changing the SD SPI pins, I can run the tutorial 1_03 up to 2_03 so far.
However, the rev D uses pin 13, you have to comment out the...