hmc6343 will not initialize

I recently purchased the hmc6343, as an upgrade for a project I had up-and-running with a LSM303. The LSM303 was getting interference, and I'm hoping the shielding on the hmc6343 does a bit better.

Because hmc6343 runs on 3.3V, I'm using a 3.3V Arduino Pro Mini. I've soldered the SCL and SDA wires, set pin 10 to LOW via digitalWrite (to use as a ground), and set pin 12 to to HIGH (to use as power). The hmc6343 only uses a few mA, so from what I can read that should work.

However, the hmc6343 fails to initialize at all! compass.init() simply does not return true, even retrying every second for 5 seconds. I'm a relative newb at this, so any suggestions would be much appreciate. The only thing I could think of would be to use VCC to power the chip instead of a pin set to HIGH, or connect the ground directly.

Add 2.2K to 4.7K pullup resistors from Vcc to SDA and SCL. They are required for I2C communications and the Pro Mini does not have them.

The LSM303 was getting interference, and I'm hoping the shielding on the hmc6343 does a bit better.

What sort of interference?

Have your calibrated the magnetometer, as required? Exhaustive tutorial here: https://thecavepearlproject.org/2015/05/22/calibrating-any-compass-or-accelerometer-for-arduino/