Intermittent very slow speeds

[#1]

Hi, about 2 weeks ago I complained of very slow net speeds. I normally get about 2Mbps-2.5Mbps. Not blisterin speeds of others but they are perfectly ok for me. However 2 weeks ago my download speed dropped to 240kbps, even slower than my upload speed. This lasted for a few days then righted itself. This appears to be happening again now. I am currently struggling to do anything on the net.
What may be causing this and what can I do to fix it? I've tried different routers so my router is not the issue. I also use linux and windows computers and all have the issue so it isn't the computers themselves.
It's getting very frustrating when it currently looks like 2-3 days every fortnight I have unusable internet speeds.

[#2]

https://portal.plus.net/my.html?action=stable_rate gives the result:
Estimated line speed:
    3.0 Mbps - Checked on 2009-03-23 02:49:44
Current line speed:
    250

[#3]

Hiya,
You mentioned that you've tried different routers, which is great.  Have you also tried wiring the router directly to the master socket, and tried changing the filter?

[#4]

Something is causing your router to resync at a very low speed which sets your BT controlled IP Profile to a very low value.
Have you plugged in any new equipment in to any telephone socket in the house recently (phone, sky box, alarm etc)?

[#5]

Quote from: Jameseh

Hiya, You mentioned that you've tried different routers, which is great.  Have you also tried wiring the router directly to the master socket, and tried changing the filter?

Nope. I'm not really sure how to do that but I could try to find out.

[#6]

Quote from: jelv

Something is causing your router to resync at a very low speed which sets your BT controlled IP Profile to a very low value. Have you plugged in any new equipment in to any telephone socket in the house recently (phone, sky box, alarm etc)?

Nope. Nothing new at all. Only thing plugged into the phone is one phone and the router.

[#7]

I think my problem looks suspiciously like this thread. Same speed too.
http://community.plus.net/forum/index.php/topic,77794.0.html

[#8]

@Jayed - I meant to connect your router to your master telephone socket via a microfilter.

[#9]

Quote from: Jameseh

@Jayed - I meant to connect your router to your master telephone socket via a microfilter.

Yeah, I just reread that. I only have one telephone socket so I guess it must be the master socket. I also use a microfilter.

[#10]

Hi,
I've just increased your profile slightly in line with that of BT.  You should notice a slight improvement if you reboot your router.
I'd recommend that you raise a fault via http://faults.plus.net as an intermittent connection as your connection drops are causing your speeds to fluctuate.

[#11]

Hi, what connection drops? Although slow, the line does seem stable.

[#12]

Keep an eye on the connection time in the router. It's possible that it is resyncing without you being aware.

[#13]

Your connection's dropped 24 times in the last week.

[#14]

Oh, I hadn't realised that. I do turn it off when not in use. So that's at least twice a day, but that's only 14. hmm.

[#15]

Thanks, that speed change has made a difference.
Should I turn my router off? I prefer not to have it on if it's not in use for a long period.