I think I found the problem! I have changed the battery used for the sensor from a 3.6V to a 3.8V Lithium-ion. I use a 5V charge pump to power the AD595 and the PIC12. The Charge Pump must have its SKIP pin high for voltages greater than 3.6V. Once jumpered to positive terminal of my battery everything seems to be working well.

I will allow the PIC12 to handle this in the future for when the battery falls below the 3.6V threshold.

I will keep everyone posted!

Scott