I just got my cheap DMM from DX. Having a few troubles in in measuring the voltage now. When I first got it, I was able to measure the voltage on lithium-ion cells. However after running some tests with on a charger (to measure the current from it), I can't seem to measure voltage anymore. I can still measure current though. Did I fry something when measuring the current on charger? I actually left the DMM attached to the charger, while it was charging.