so finally figured out the issue igyes, when packet loss happens on TCP the packets are re transmitted. In case of games, this may result in timeouts.
I think that just means that those routers have rate limited ICMP replies. If there was really packet loss on those hops, it should have been reflected in all further hops as well - as every packet from further on, transits through those routers to reach the OP.Seems the problem is at bsnl end (4th hop)?