System feedback coming thru speakers.....help

All great points, Lloydelee21! I actually did some additional reading on here late last night and did some of your suggestions early this AM.
So, when having just the amp and pre hooked up and turned on (CD/DVD still connected but now turned on) there is no feedback, even turning volume up on pre.
everything else is disconnected from pre, as well as power. I also disconnected tv power, etc from system.
I DO have a power strip in place as the outlets are all two prong in this house. SO, I have to have a "3 to 2" reducer on the end of the power strip.
still getting same thing! ugh! if volume just barely turned on, music is fine. but as you turn it up to even 9 o'clock, the woofer starts to "pop" and there is static coming from mid and tweeter......both speakers!

I am not certain how old tubes were with pre amp, but I just put them in, and they (I believe) were well labeled for placement (I never put tubes into a pre before).

additional thoughts?

To make sure i got it right...pre amp (on), amp (on), DVD (connected but off), turntable (disconnected and off)...no buzz no matter how loud you turn it up. That's GOOD. Once you put the DVD on, you get noise? If so, it seems to be either: a) the power strip, b) the connection between the DVD and the preamp (ie, the cable or the actual RCA in-jacks in your preamp...try different onces), or c) the actual DVD player itself. Try to avoid the 3-2 reducer on the end of the strip...it means you have no ground. that could be part of your problem?

If your amp and preamp run thru power strip just fine...plug DVD player separately into wall direct and see what happens.

+1 on getting your equipment into a grounded socket. I'd do that pronto.

If you are renting, I'd talk to your landlord. Having safe electricity is a pretty reasonable request. If you own, then I'd spring for an electrician to give you some grounded outlets.

All great advice, thx! yes, renting......just moved out of house that we built 6 years ago, so been a bit spoiled on actually 21st century technology, vs. NINETEENTH!!!! :) I have a call into my electrician today to get addressed, either way. Will do further isolation testing tonight as well to see if I can figure this out. so frustrating, but I think you are both on the right track for me. Thank you so much! Jason

Sounds like you have a "cheater plug" between your power strip and outlet. I would get rid of that. You can have a standard grounded 3 prong outlet installed in place of that 2 prong. You would run a "ground leg" from the ground terminal of the new outlet to the steel electrical box via a grounding screw to the threaded hole in the back of that box. Since the cabling is probably BX, it would be self grounded to the main panel box.