Do i have a speed problem?

[#1]

HI,
A few months ago I signed up to plusnet unlimited fibre broadband and was told from two different people I could expect speed of 68 down and 20 up.
When the day came for BT to install my broadband the engineer apologised for being late as he said he was having alot of problems with my phone line at the exchange, there was also another engineer with him.  The engineers replace my phone socket with a new one and then began to run tests on it, which i overheard had failed, they then ran the test again twice more and it passed.
Since then ive checked my speeds several times and noticed they`ve never managed to get any where near 68 down 20 up, the highest ive seen is 50 down once and 14.4 up with the lowest being 29.82 down and 10.21 up (i believe i average at 40 ish down and 13 ish up) I checked the speeds at different times and they dont seem to be constant for instance il have fast speeds one day at say 7pm then slower the next day.
I was just wondering is this normal not to have those speeds quoted, i know on normal broadband (copper?)  companies quote a speed but nobody ever gets near it, but i though on fibre that wasn't the case.  Also is it normal for speeds to fluctuate that wildly?  Or am i just being paranoid with over hearing the engineers saying they had issues with my phone line.
Thanks alot.

[#2]

Hi Tic174,
If your estimate was 68Mb upon sign up, then we would be happy to take a look at things for you. Of course we couldn't say whether or not there is any aluminum cabling on your line, however I think the speeds you are receiving at the moment is far too low given the original estimates shown.
I would complete the Broadband Fault Checker which can be found at http://faults.plus.net - once you complete this, our Faults Team will investigate further for you.

[#3]

What plusnet are failing to tell you is that the router they supply is a toy, you need to buy a better one, BT Home Hubs (FTTC) work fine.

[#4]

My PN router worked absolutely fine on my 100/15 connection. No issues whatsoever. I just upgraded it as I wanted increased functionality and a slightly improved wireless signal in the corners of my house.

[#5]

@inhost
To be fair, that does rather depend on what the underlying problem is. Whilst I'm not a big fan of the TG582n (which I assume the OP has), it seems to work fine for a lot of customers, as AndyH has said. Wifi on this router doesn't seem to perform well under certain conditions - I'm guessing that may the problem you experienced...?
So hopefully Tic174 has measured throughput using a computer connected to the router using an ethernet cable. Otherwise it's possible the limited throughput could be caused by wifi problems rather than any inherent problem with the line.

[#6]

Hey guys, Thanks for the fast replies.
I think ive found the source of my problems, I have to use homeplugs to connect to the router, but when i switch them out and plug my computer directly in to the router via a very long ethernet cable my speed goes from 20.35 down (new lowest ive tested) to 57.28 down then when i switched back to a different set of homeplugs i get 21.56.  So clearly i seem to be having some sort of problem with my wiring in my house.
Thank you for all your help its very much appreciated.

[#7]

Unfortunately this seems to be a regular problem with homeplugs! I've often wondered if the problem is caused by poor smoothing on the modem power supply, which is feeding the homeplug signals on to the power rails of the modem. A good mains filter on the feed to the modem and router might solve it...  I'm less inclined to believe it's RF noise from the homeplugs, but it's possible. Perhaps someone else has found a solution?