Hi all, The hum while not touching the guitar metal body or string, was so high and irritating! The cheap amp has two wire (no earth) mains line and has linear Xformer. I watched dozens of videos about noise gate, ground loop problem, shielding guitar's internal chambers etc. All of them looked complicated or time consuming. Today what I did is: replaced two pin supply cable into 3 pin (with earth) and connected guitar input 'ground' to earth through 10nF 1kv capacitor. Amazing! I eliminated the hum! Is this a good way to do? Do it need to connect the earth directly to 0V DC too, for further improvement? or throught the another 10nF cap?