Have to turn on-off mobile data every now and then so that mobile data works! phone: Samsung Galaxy Ace 3 (gt-s7272) (rooted)

From the moment that I have bought my phone the speed of internet via mobile data is so weak; other phones in the same location as mine can use the same APN settings without any problem and their net speed is good. But the strange thing about my phone is that I have to turn-on and off mobile data now and then(after for example 10 minutes) to prevent internet speed from dying! after re enabling mobile data net speed is good but as I said just for nearly 10 minutes and I had to turn-on and off mobile data again!

any idea why it is so and how to resolve it?
You mentioned that you are rooted, just try editing your build.prop file with Internet tweaks. It might help. You can get various build.prop tweaks here. Have a look..
Collection of build.prop tweaks

Relevant tweaks (11 and 12) for better 3g/internet speeds from the link:


  
  Signal (3G) tweaks
  
  Code:

ro.ril.hsxpa=2
ro.ril.gprsclass=10
ro.ril.hep=1
ro.ril.enable.dtm=1
ro.ril.hsdpa.category=10
ro.ril.enable.a53=1
ro.ril.enable.3g.prefix=1
ro.ril.htcmaskw1.bitmask=4294967295
ro.ril.htcmaskw1=14449
ro.ril.hsupa.category=5

  Net speed tweaks
  
  Code:

net.tcp.buffersize.default=4096,87380,256960,4096, 16384,256960
net.tcp.buffersize.wifi=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.umts=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.gprs=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.edge=4096,87380,256960,4096,163 84,256960