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INA826: Instrumention Amplifier gets damaged

Part Number: INA826


i am developing an constant current source. The following picture shows the concept.

The current is given by dividing the DA-Converter-Voltage with one of the resistor values (SHUNTS). Which resistor is activated is controlled by an microcontroller. Also the DA-Voltage ist controlled by the microcontroller. The Current flows through P$1. The INA826 has a supply voltage of 30 V DC, Rg is not connected, so the gain is 1. Pin 4 of the INA826 is allways connected to 30V. Pin 1 varies between 28 and 30 V. That means the maximum output voltage is 2 V. 

Now the Problem: The INA826 gets allways damaged. I cant explain why. I tried other Instrumentation Amplifiers from other companies at the same conditions and it worked fine. Also I tried the INA828 and it gets damaged too. As soon as voltage is turned on, the INA826 blows. I damaged allmost 10 devices. 

Is something wrong with the wiring of the INA826?