i been using my streamyx account for 5years in different area of cheras which is tmn yu lek and current house nearby tmn connaught and having same problem untill last year 2 chinese girl n 1 malay technician came my house, i even show the no problem at morning but night worse and my latency in the games i played then they say they will check the port and for that years till last week i had smooth n no disconnection problem and they upgraded my package to 1.5mbps from 1mbps that why everytime i do speedtest i got 1.2mbps at malaysia or US till last week.
and you feel happy getting 500+ kbps, you using 512mbps or 1mbps?, streamyx technician can actually done their job but just they dont really want it.