Expensive Shielded RJ11 cable here, also at PC World Stores. Warning this cable behaves like a coiled spring, the only way you can control it is to nail it down!
I use a 15-metre BT extension lead it all works just fine.
Purchase a good quality ADSL microfilter it makes all the difference.
The cable that comes with a router is typically less than 1.8m and therefore is unlikely to suffer that much interference. It would only be in exceptionally noisy environments where this is likely to be an issue. At the end of the day 9 out of 10 consumers are not going to take a blind bit of notice what cable is included so the bean counters will go for the cheapest option.
The ADSL Nation XF-1e microfilter is a great product and really does work well, I now use no other make.
I use a standard 15 metre BT approved telephone exstention lead, not the micro type, so that I can have a telephone by the PC, it all works fine and most of the time there are no (Fast Path CRC Errors) indicated by the router.
My stats this morning for my 2Mbps fixed speed connection.
ADSL Status Status Configured Current
Line Status --- SHOWTIME
Link Type --- Fast Path
Data Rate
Stream Type Actual Data Rate
Up Stream -------288 (Kbps.)
Down Stream ---2272 (Kbps.)
Operation Data
Operation Data Upstream Downstream
Noise Margin ----30 dB -----28 dB
Attenuation -----27 dB -----26 dB
Defect Indication
Indicator Name ----Near End Indicator - Far End Indicator
Fast Path FEC Correction --------0 ----------- 0
Interleaved Path FEC Correction -0 ----------- 0
Fast Path CRC Error -------------0 ----------- 1
Interleaved Path CRC Error -------0 ----------- 0
Loss of Signal Defect ------------0 ----------- 0
Fast Path HEC Error -------------0 ----------- 0
Interleaved Path HEC Error -------0 ----------- 0
Statistics
Received Cells -------------3086
Transmitted Cells ----------1509
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