Boost gauge

[FEED Rocket]

Hi guys, ive got a greddy digital boost gauge and sometimes it goes a bit mental and registers at 1.2 bar giving me a red light, when my fc commander is only showing 0.9 bar. I know my commander is right, but im just wondering what it could be thats making the gauge go tits. I only happens once in a blue moon but really narks me.

 

[startrack]

Where about do get the pressure reading from for the gauge and the commander?

 

[FEED Rocket]

Im not sure, but they both must get the signal from different places as they are both reading different.