Speed is no way near ip profile but it was when I joined PN

[#1]

Why does my speed not hit the speeds it used to. When I joined PN on Jan 10th 2013 I was consistently receiving 75-78mbps but now it struggles to get over 40mbps. Im less than 25 meters from the fibre cab. My wifi signal is 99%, the connection between the router & laptop is 130mbps. I am on a wifi channel that no one else is as I have looked using inSSIDer. I have done a wired test & no difference. I have attached a screen shot so you can all see. I submitted a fault last week but was told everything is fine. Surely my connection speed should not halve when I am so close the Cab.
Im no telecom engineer but something is not right. Can PN turn up the power or something along them lines?

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[#2]

Just done another speedtest. My speed drop coincides with my phone line being switched across from my previous isp. would any line settings have been reset?

[#3]

Hi,
It's possible that the work on the line caused a burst of noise/interference which in turn caused the DLM system to lower your line's profile. I'm afraid there's nothing we can do manually to speed up the process, but it should sort itself out and get back to its previous levels in a few days - we couldn't be any more specific than that though.
If it doesn't we could look at raising a fault but we'd rather wait at least a few days for the profile to improve before doing that.