Avenger reg pressure issue

My brother has an Air Venturi Avenger that recently developed a strange problem. AS the air pressure in the tank gets below 2500, the reg (set at 1900PSI) will start to creep downward with the bottle pressure. It actually goes as low as 1100 PSI, causing obvious problems. I'm thinking a possible bad or very inaccurate tank gauge, reading higher than it actually is ?? Your thoughts ? I'm not too familiar with this model. I've only handled his a few times. I don't know what else would make the reg lose it's set point. Your thoughts ??
 
Mine does the same thing just not that extreme. I talked to Stacey at Air Venturi and she said it was probably the guages. They are not precision guages and may be reading higher/ lower than actually showing. You could try ordering a replacement for the pressure side. The new one may match the regulator side better. Or order both and see if you get lucky.
 
Not saying this will correct your problem. But may be worth trying. You can always give Air Venturi a call.

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