Pop filter, reverse polarity protection and power filtering

[formerMember1]

I put the one probe to ground and red probe to the switch lug where the output wire from ciruit is going and i just get readings in milivolts that never stop on a reading,.. it just keeps changing... sometimes it will keep goin up on the meter from no milivolts, up to 36milivolts then it will go back to nothing and keep displaying differnt stuff....

i don't know what gives... if anyone can give advice to help find the problem please do...