I've been getting very poor speeds the last few weeks, normally sub 0.5Mbps. Just ran another speed test at 4am and it's registered 0.42Mbps. I'm getting this speed both through wireless and wired on all my devices such as my smartphone and laptops.
The Status page doesn't mention any faults in the area (15).
Your downstream power levels are too low on a few channels and your upstream power levels are too high.
You will need to contact VM for resolution, either by waiting here a few days until a VM Forum Team Member picks up the thread, or give them a call on 150 from a VM line or 0345 454 1111 for a quicker response.
Sorry to read that you are experiencing slow broadband speeds. I know how frustrating this can be.
As griffin mentioned the downstream power levels are too low, the upstream power levels are now within range which is good. There have been a high amount of T3 time-outs within a short space of time also. I've sent you a PM (purple envelope icon, right corner) requesting some details to book an engineer to check this for you.