Katha testai ho, lexicon ma jaau. A friend once said, "How do you know whether you are from the valley (Kathmandu) or the hills? If the person writes Xa for chha, then he is from the hills." He didn't say what the valley people write. You said you live in KTM so I am going to show him this as a proof he is wrong. Btw, I don't agree about valley and outside, but I do agree Xa is NOT chha. Xa it ja. Hunxa thus becomes Hunja.