[codefox1]

The dual power switch (S2 on the schematic) on the back of the control has nothing to do with volume adjustment (R4 on the schematic) and is not electrically connected to it slyhough they are ganged together. After you bypass the switch connections you can use either one to handle the AC supply. Test the switch you want to use first, one of them might be defective.

Do not touch the chassis when power is applied. All transformerless radios are dangerous no matter how you plug them in. If you use an isolation transformer you are a little safer, but still don't touch when power is applied.