Jittery Memsic 2125

Sunflower

We are using a couple Memsic 2125 for tilt feedback as a safety to prevent an autonomous large solar dish from ground torching and starting fires. They replace the axial pots for reliability. On multiple readings each MEMS axis gives jittery values of plus and minus several binary degrees, including horizontal. Is this normal? The power supply is stable (MMC carrier with caps, no motors yet, no noise, battery supply, stable temperatures), the wires to the MEMS are several feet long with no shielding, BS2p is with code from docs (read them all plus forum archives). I also noted excursions far above (110%) expected values on one sensor axis. These issues can be smoothed out with data averages, ATN, and MAX MIN. But still, are jittery MEMS normal? Are they reliable for the long term?