Just got my Singtel modem upgraded to their latest PACE a5520n modem.
If you have an Xbox360, you will have problem connecting to Xbox LIVE (both wired and wireless) and play your games.
The only way to fix this is to call Singtel hotline (1688) and upon verifying your details, ask to be transferred to the technical helpdesk (depending on whether you’re having ADSL or Fibre service).
The Customer Care Officer will request that you leave your modem on so that the update of firmware can be done live. It takes about an hour (or maybe lesser) for the process to complete. You will see your modem lights changing/flickering to orange/green and this is part of the process.
When the lights turn green and are stable, restart your modem (by unplugging and plugging back the power cord).
Wait a few minutes and once your PC/laptop/mioTV (if you have any) is connected to the internet, the same can be done for your Xbox360.
For some reason, I couldn’t find the firmware from PACE website so I could install myself.
Hope this helps.