Please help! Tube amp issue


I am extremely new to building tube amplifiers. I've never done this before, but this concept intrigued me alot, therefore I decided to build one. I followed a schematic of a 20W pc tube amplifer. To my knowledge, and to checking my work multiple times, I have followed the schematic religiously. I think it's from an old Magnavox amplifier.

When the amp switches on, there is an insane amount of noise, even when there is no audio input given. The only modification I have made is that I have changed is the main power tranformer's primary voltage due to where I live. (120x2)

I'm not allowed to post the schematic's diagram, but I may link the page:

http://www.wkinsler.com/radios/7tubeamp1.html

If anyone could please dissect the schematic to see if there could be a potential problem with the design itself, that would be fantastic.
I have also takena a video of my amp groaning the noise away to glory: (One of the pre amps do not work, but then i disconnected one side of the amp, and the noise still existed)
https://www.youtube.com/watch?v=Myj-aIommmA
ilya_

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