Remind me what range of acceleration in g can the accelerometer measure? (spec sheet)
I'm using the 1.5g range, with a sensitivity of 800 mV/g. Maybe the sensitivity is to high? I can select other ranges: 2, 4 and 6g, but with lower sensitivity.
Also do you have a stable surface for the accelerometer or is it too close to a computer? The computer cooling fan could be a source of vibration. May be important if your accelerometer has a high sensitivity.
It was close to a computer. I can try to put it further away from it.