my psones keep breaking for some reason

[devileyebrows42]

When i test my psones several times they become dysfunctional after a while. they look perfectly fine, but when i test the positive and negative power against the multimeter... there is no circuit recognized. but when i try a different system which i havn't used before. it recognizes a circuit. I can't seem to find out what is wrong with it. Hooking one of the tested consoles up to a battery no longer works. (This happened to 2 of my systems already). can anyone help?

[silver]

if your running off batteries remember to charge to the max,
and otherwise, i had this problem today, when mine didnt start up, but i just left my battery charging for a while and it worked.

[devileyebrows42]

What i don't understand is why my multimeter doesn't recognize a circuit when i touch the positive power and negative power leads, but it does on the other system i have. has anybody else had this problem?