Thanks for finding that sync rate, it clears things up. 😛
I am afraid to say, but you already know the line quality is terrible, due to which you have such a poor sync rate. At 42dBm attenuation, ideally you can have a sync rate as high as 8.5Mbps without major issues. However, you are doing only 2.3Mbps, what is worse is your SNR is an extremely low 6.4dB, anything under 6dBm means no connectivity possible. There is so much interference/noise that there is literally no space left for more bandwidth.
Unless MTNL cleans up your line of this noise/interference there is no way you will get anything better. Being MTNL, the sun would probably have to rise in the North before they ever did that.
I am afraid to say, but you already know the line quality is terrible, due to which you have such a poor sync rate. At 42dBm attenuation, ideally you can have a sync rate as high as 8.5Mbps without major issues. However, you are doing only 2.3Mbps, what is worse is your SNR is an extremely low 6.4dB, anything under 6dBm means no connectivity possible. There is so much interference/noise that there is literally no space left for more bandwidth.
Unless MTNL cleans up your line of this noise/interference there is no way you will get anything better. Being MTNL, the sun would probably have to rise in the North before they ever did that.