Audio Systems: freaky stereo system, pioneer radio, volt meter

Question
1995 Subaru Legacy.  My stereo will freeze up, power light stays on, LCD display goes blank, and I can't push any buttons or power off.  Occasionally it will turn the volume down by itself, then turn it back down (though this could just be it freezing for a short time as the radio coming on shows volume coming up).  I had replaced the Pioneer radio in the car because it was doing similar (replaced with cheap walmart radio).  Sometimes it will only freeze for a minute, sometimes for hours. Sometimes if I turn off the car and then back on it will fix it, sometimes not.  Happens with CD, radio, aux, whatever.  Before if I would touch the buttons/volume knob it would freeze up but lately the buttons haven't made as much difference.  I don't know much about this so any help would be much appreciated.

Answer
sounds like there is a problem with the power or ground there is not enought current in the lines, a volt meter is not going to help much, because it will show 12 volts in the line
first change your ground wire runna wire with a ring terminal and a screw into the metal chasis  most likely this will solve your problem