That must be a long or very poor line you are on.If the line is genuinely not capable of better speeds than that it would have been better to have a fixed rate connection. BT have a system called Extended reach and I know of a case where they got a 2MB connection on a line that is 11 miles long.
You need to get your line stats checked to see what you "should" be able to get.Then you also need to look at the miriad of things that can cause bad throughput on your service. House wiring,SkyBox,bad filters,wires along side your ethernet /router cables, the ring/bell wires still being in use in the BT cable inside the house,all these can have a dramatic affect on your BBMax.
If you have an NTE5 BT master socket you can do 2 simple tests,1) remove the bottom cover (2 screws) and plug your phone in to the test socket inside ,if you hear any noise from this socket there is a line fault that BT have to fix.
2) Plug your router into this socket and check your BBMax performance from there,this eliminates all the wiring in your house and you may well see a big difference.
Take a look at the long list of sites I posted in this thread here....
How can I find the best performing provider my area? there is a lot of detailed help there and using the help sheets at adslZone,Kits and Idnet will show you how you can get better results.
Find out how far you are from your exchange, get your router stats,the synch speed,attenuation and SNR margins are important, run a BT speed test,these are vital if you are going to tackle BT they do not accept any other tests and the results are recorded. Go to
Test Result and enter your phone number,then you enter your isp username,the results will tell you a lot about your line and you can copy them.
One simple thing that can help your speed,do not shut your router off,leave it on 24/7. Many people power on/off dozens of times a day and this will drive down your speed as the DSLAM at the exchange will register a line fault and drop your line profile,thereby killing the speed.