i hate to ask but I Really Need Help


I recently purchased a plinius 8200 and i am having a serious hum problem, not the kind that is bearable when the music is on, something is not right. To get to the point i am going to list all the facts that may be relevant and what i have done so far.
-i live in the south in a house that is 60 to 80 years old, i do not know anything about the wiring, i rent so any improvements to the system are out of the question.
-i switched the old two prong outlet to a three prong, i connected what appeared to be ground wires but i do not know if the are truly grounded.
-i have tried three sets of interconnects, different speaker cables, using cheater plugs, a RGPC 400, a PS ultimate oulet and different power cords in a number of different combinations to try and solve the problem which i have been sucessful in dealing with in past apartments.
-occasionally when trying different connection combos i have powered on the system and the hum is gone but if i change the volume by touching it sometimes comes back, sometimes it comes back with out being touched.
-HELP! i am completely unable to use my system at this time
i will try to promptly answer any questions that may help
mkaes
Here's one more "tip" that i overlooked. Agon member "Brick" posted this tip over in another thread about "dedicated AC lines". Kudo's to Brick for pointing out the obvious. It was so obvious, i didn't even mention it in this thread at all. I'm good like that sometimes : )

Before starting on anything else, take your multi-meter and turn it to AC voltage ( 200 volts if manual ). Measure your AC voltage and see what you have. It should be somewhere between 115 volts and 123 or so. Getting up much above that can cause problems with some gear, so it's not a bad thing to check this once in a while. Going below this can also cause problems, but this would be more of a sonic problem than one of potential damage.

For those that don't know how to do this, you simply insert one probe tip into the outlet on the wall and the other probe tip goes into the other slot. It does not matter what slot the red or black goes into as AC works differently than DC. Bare in mind that i'm talking about the "slots" here and not the "hole" for ground.

After measuring the AC voltage, pull the probe tips out of the outlet and adjust the multimeter to measure DC voltage ( also 200 volt range ). Insert the tips into the outlet just like you did before and see what the multimeter reads. Hopefully, it should be phenomenally low i.e. "0" or "0.01" etc... The higher the reading that you get, the more DC that you have on your line. While most gear can tolerate a small amount of DC on the AC line, other gear can buzz, hum or run very hot. As such, this would be one more thing to check if your system starts making noise out of the blue. Keeping track of data like this in your "audio log" might come in handy. Should you need specific dates for reference when trying to resolve a problem like this with your AC provider, you'll have all the information you need at your fingertips. Sean
>
Sean, Thank you so much! This is why AudiogoN is such a tremendous community. I have added this thread to my scrapbook so I can refer to it whenever I need it. Also glad Mkaes that your problem is resolved. Sean, heartfelt thanks from the community (to the extent that I can speak for us all!)