Some volt meters require that you place a resistor across the input leads. The resistor is usually a 1 Meg Ohm or a 10 Meg Ohm value. Check the instrucions for the meter... If it doesn't say specifically that you need to, you can try placing a 1 Meg Ohm resistor across the input to the meter to see if that solves the problem. It won't hurt anything to try.