BA02 sensor now producing strange results

I have not tested these sensors in water yet.

My first BA02 sensor

This sensor produces atmospheric pressures that seem too high. I have it on the bench now and its been showing around 1034mb all afternoon. Meanwhile I have two other different types of pressure sensors ( SparkFun Barometric Pressure Sensor Breakout - BMP180, and a SparkFun Pressure Sensor Breakout - MS5803-14BA) on another Arduino showing between 1005mb and 1007mb. I am tending to believe these two sensors.

My second BA02 sensor

This is really odd. I powered it on again this morning and initially it started to show up atmospheric pressures close to my other sensors. However, after monitoring the output I could see it drifting down, both in temperature and pressure

e.g. for example at
11:33 Prs of 924mb, tem 22.24 degreeC
11:49 Prs of 874mb, tem 21.48 degreeC
12:10 Prs of 816mb, tem 20.67 degreeC

13:10 Prs of 656mb, tem 17.69 degreeC
13:36 Prs of 600mb, tem 17.64 degreeC

by 14:18 it had reached 468mb.

Any ideas on what to to try next?