I have a different reason for this problem. What you are facing is called a dead spot in the gas pedal travel.
In your car's carburetor there are different jets. As the gas pedal is pressed, more air is introduced into the engine. As more air flows through the carb, fuel is mixed into the air with the ratio of about 1:14 (fuel:air) is maintained. One fuel jet cannot manage the 1:14 ratio from idle to full throttle. Hence there are 2-3 jets provided with different size holes. As the gas pedal is pressed, fuel progressively flows through 1st, then 2nd and if there is a third then through 3rd jet - each jet has larger holes than the previous one. In a perfect carb set up as the car accelerates, the change from one jet to the next is not felt. But if the jets have been messed about, then when fueling duties from one jet to the next happen, the engine stumbles (as if it is about to die).
Not sure what this noise is. I dont think is has anything to do the carburetor.
Assuming that the jets in your carburettor are the original ones and no "ustaad" has cleaned them with a steel wire, your first step would be to make the idle mixture a bit rich. That should reduce the engine stumble as the carburetor transitions from idle jet to main jet.
