My board has a 5V and 3.3 V.
I directly connected the MOSI, MISO, and SCK of the SD card to the MOSI, MISO, and SCK of my arduino.
I also directly connected the VCC pin of my SD card to the 3.3V of the arduino.
After connecting everything, I checked the voltage at the 3.3V pin of my arduino.
I used a fluke to measure the voltage. I got a reading of 4.3 volts.
I'll try the 100uF. It might work.
Also, I'll try connecting the audio out to pin 9.