Probably it is due to the distance from your house to the exchange... You can check whether your line is 50% fiber optic (from the exchange to the remote cabinet DSLAM) or purely 100% copper by accessing TM SAMS WEBSITE. Just enter your streamyx username or phone number and you will know it. For partially fiber line, the green F symbol will appear at the J or Jumper area, meanwhile for the fully copper line, the green TICK symbol will appear instead of F symbol. You can see the attachment below for the example when your line is partially (or 50%) fiber.

It is recommended that you change the modem because you said that your house is big. You're using 4Mbps, and I heard that there are many problems involve around the TM Wifi modem (especially Riger and Innacom one). But you need to spend a bit... Maybe TP-Link TD-W8960N is suitable for you....    Depending on the seller, and the most cheap one that I found is RM122 from one reputable seller at Lelong.my... Or perhaps, you can do the survey at the Lowyat itself...  

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Basically what can I see is there are three "transaction" done on your account on the same day, which is 25 Nov 2011...

First, you terminate your line, and it seems your jumper is located on the street cabinet (by the green F sign there)..
Then the new installation process are made by TM, and your jumper suddenly change maybe from the fiber cabinet into the direct copper line to the exchange...

Lastly, it seems that there are some problems regarding your port, because the RED X mark available on your jumper status. You better call the mr Desmond and asked him what is the problem for your port... Or maybe they've done some 'mistakes' on the system... because you said that your 4Mbps application are succeed but why the SAMS status shows like that...