Extremely slow broadband the last 3-4 weeks

Question

Hi 
I've been a BT total broadband customer for years. I've not moved house for more than two years. I used to get actual download speeds in excess of 3mbps, I now struggle to get 300kbps. This has only happend in the last few weeks. 
I've phoned BT's support and been through all the checks several times, microfilters, master telephone socket etc. I was put through to BT engineering who say they've made some changes to improve the speed but nothing has happend in real terms to the speed. They then said they'd call me back and haven't.
Can someone here help me? I used to enjoy reliable, high speed broadband but have had nothing but a dribble for the last few weeks. Just to reiterate - nothing has changed within my house. Everything is exactly how it was when I used to enjoys 10 times the speeds. At the moment it is essentially unusable except for basic web browsing. 
Here is a recent speedtest taken today at 8.58pm, more than 3 days after the last router reset:
Test1 comprises of two tests
1. Best Effort Test:  -provides background information.
Download Speed
233 Kbps
0 Kbps
500 Kbps
Max Achievable Speed
 Download speedachieved during the test was - 233 Kbps
 For your connection, the acceptable range of speedsis 100-500 Kbps.
 Additional Information:
 Your DSL Connection Rate :572 Kbps(DOWN-STREAM), 440 Kbps(UP-STREAM)
 IP Profile for your line is - 350 Kbps
The throughput of Best Efforts (BE) classes achieved during the test is - 24.15:15.86:59.99 (SBE:NBEBE)
These figures represent the ratio while sententiously passing Sub BE, Normal BE and Priority BE marked traffic.
The results of this test will vary depending on the way your ISP has decided to use these traffic classes.
2. Upstream Test:  -provides background information.
Upload Speed
343 Kbps
0 Kbps
440 Kbps
Max Achievable Speed
>Upload speed achieved during the test was - 343 Kbps
 Additional Information:
 Upstream Rate IP profile on your line is - 440 Kbps
We were unable to identify any performance problem with your service at this time.
It is possible that any problem you are currently, or had previously experienced may have been caused by traffic congestion on the Internet or by the server you were accessing responding slowly.
If you continue to encounter a problem with a specific server, please contact the administrator of that server in the first instance.

Answer 1

Apologies... Here with more details:
ADSL line status<script type="text/javascript"></script>
Connection information<script type="text/javascript"></script>
Line state
Connected
Connection time
1 day, 18:02:17
Downstream
572 Kbps
Upstream
440 Kbps
ADSL settings<script type="text/javascript"></script>
VPI/VCI
0/38
Type
PPPoA
Modulation
ITU-T G.992.5
Latency type
Interleaved
Noise margin (Down/Up)
24.0 dB / 31.1 dB
Line attenuation (Down/Up)
30.0 dB / 15.5 dB
Output power (Down/Up)
0.0 dBm / 12.6 dBm
Loss of Framing (Local)
0
Loss of Signal (Local)
0
Loss of Power (Local)
0
FEC Errors (Down/Up)
889 / 4294967264
CRC Errors (Down/Up)
0 / 2147480000
HEC Errors (Down/Up)
nil / 0
Error Seconds (Local)
10