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[on:]

Reads on an SD card can be heard through the Dac.

Arduino Due
AdaFruit Micro-SD Breakout Board (Board -> SPI and Pin 10)
AdaFruit MAX98306 Amplifier (Board -> DAC0, GND, 3.3V)

Things I've tried to get rid of the noise.
1.  Redid wiring using Jameco connectors -> still noise.
2.  Bypass Amplifier to externally amplified speakers -> still noise.
3.  Tried Dac0 and Dac1 -> noise on both.

I've attached a picture of the wiring.

Any help is greatly appreciated.

[Reply #1 on:]

That could be caused by grounding loops. Try to connect each module's GND wire to a good decoupled "single ground point" ("star" topology). Maybe a decoupling of each module's power (small resistor in series and capacitor to gnd) could help as well.

[Reply #2 on:]

How are you powering the board? I had extreme noise on a Bluetooth A2DP module connected to a Due, which turned out to be caused by powering the board by USB. When powered by a 9v battery into the DC jack the noise disappeared.

[Reply #3 on:]

I've tried powering the board using both the USB and a 9V battery and using a star topology for ground, but the noise is still present.  I haven't tried decoupling each module's power yet, but I'll try that next.