MPU6000 too many INT pulses

Hi,


We have added the MPU6000 to our latest revision of our PCB.
We had it working on a prototype (wired to the previous PCB) and it worked fine.
There are very few hardware differences, but with the new PCB we have a problem with fast INT pulses!
Basically there are too many of them coming too quick.
We are using the same settings as we used in the prototype:

#define SMPRT_DIV 0x09 // We want 100Hz so set to 9: 100 = 1000/(1+9)
#define CONFIG 0x03 // FSYNC not used + Low pass Filter = 44hz
#define GYRO_CONFIG 0x18 // Gyro full scale range = 500deg/sec
#define ACCEL_CONFIG 0x10 // Accel full scale = 8g/high pass filter = 0
#define INT_PIN_CFG 0x80 // Int pin active low/push-pull/50us
#define INT_ENABLE 0x01 // Enable Data ready interrupt
#define USER_CTRL 0x01
#define PWR_MGMT_1 0x00 // Used to put into sleep mode + clock source
#define PWR_MGMT_2 0x06 // Switch off unused gyros

The problem is that we are expecting a non latching low INT pulse every 10msec but they are coming about every 129usec, but that varies too.
The i2c comms seems to work fine, when we tried changing to latching INT pulses there was another INT as soon as we had read the previous readings.

I am wondering if there are interrupts coming from elsewhere?
The INT_PIN_STATUS register has a value of 0xD3 every time we read it, indicating a FF_INT, MOT_INT, FIFO_OFLOW_INT and DATA_RDY_INT however we only enable DATA_RDY_EN in INT_ENABLE?

Could the others be causing this and if so how can I switch them off I thought they were all off as default?

Thanks

Ian