Plexi Crankling & Squealing Noise

[vahid_vs]

Thanks I cleaned it up but I just can't fix the Volume 1 problem, I took it out and cleaned it up but it didn't make any difference, any suggestions?

Thanks,
Vahid

[neikeel]

Thanks everybody, after changing the power socket with a new one, and shielding OT primary wire, the noises went away.

Now I'm trying to fix the problems the amp had before, when I close the Input I volume all the way to 0, I can still here the sound of guitar, and when I hit the the standby switch to off it makes a popping sound.

The sound through the pot when on 0 is entirely normal - do not try to get rid of it - you will fail

The pop can be helped by a snubber cap (1000v 0,05uF) between the HT fuse tip and ground. Some amps also benefit from a 4k7 or 5k6 swamp resistor between each output valve grid wire (usuallly a green and an orange) and the socket. Look at some of the builds and you will see them.

The snubber is the brown Hunt's you see here: