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chriscc
2009-01-09, 04:13
Hi all,

I have what I suspect is a network cable problem but I'd be very grateful for any hints/tips from the forum (before I give up and resort to wireless, which is a fairly weak signal).

Here's what I've tried:

I plug my Boom into an ethernet wall socket. The cable from the wall socket runs back to a cable cupboard where it terminates and I've patched it into a Netgear unmanaged switch.

When I select wired ethernet on the SB setup it does (seemingly randomly) one of two things - (a) it says "the network cable appears to be disconnected"; or (b) it gets past that step and fails to find itself an IP.

Failing to even detect the network cable made me concerned about the CAT5e cable itself. A cable test came up fine for all 8 pins (my cable tester is just a cheap 'pin' tester, it can't certify the cable for ethernet use). I also tried an 'audio over CAT5' gadget and that worked fine.

So I conclude that the copper pairs are all connected but for some reason the cable is not up to scratch - maybe some crosstalk or interference or something I don't understand.

Note - there's loads of other stuff in the house hooked up to the same switch and it all works well. I've also tried changing around the ports used on the switch in case of a duff switch port. Finally, the SB connects fine if I move it to the cable cupboard and plug it directly into the switch (although doesn't work so well there as an alarm clock...).

My questions are:

- Can I force the Boom's network interface to 10Mbps in the hope a slower speed makes the cable usable?

- Can I force half duplex or some other clever setting that reduces speed but increases reliability (I'm only using for compressed audio playback)?

- Can anyone see anything I'm missing?!

Many thanks!
Chris

alZmtbr
2009-01-09, 05:16
perhaps the wall socket connection itself is 'flakey'? Do you have a loopback connector? If so, plug it into the socket and see if you get a link light at the switch end? Yo do get a link light when the SB is plugged in, don't you?

How is the switch 'uplinked' to the router, if any? Some devices still need a 'default gateway' to function properly - arp broadcasts seemingly not being enough.

Good luck!
Allan

peter
2009-01-09, 05:40
alZmtbr wrote:
> perhaps the wall socket connection itself is 'flakey'? Do you have a
> loopback connector? If so, plug it into the socket and see if you get a
> link light at the switch end? Yo do get a link light when the SB is
> plugged in, don't you?
>
I agree that the socket connections are more likely to blame.

100 mbit ethernet uses only 4 wires of the 8, so you might try using the
other 4. You can do that by using two of these 'splitters':

http://www.duxcw.com/digest/Reviews/Network/ats/index.html

Regards,
Peter

SuperQ
2009-01-09, 09:55
You may also have a wire order mismatch. For ethernet you need to make sure the color pairs match (generally TIA/EIA T568B standard) in order for the signal to make it to the other end. If you swap the colors, you will end up with crosstalk that will make even 10mbps fail. Changing the duplex won't help (that's just an end-device capability issue, not related to signal strength)

pfarrell
2009-01-09, 10:05
chriscc wrote:
> - Can anyone see anything I'm missing?!

Try running a fresh cable outside the walls from Boom to switch as a
test. Change anything?
If that works well, plug same cable into wall jack and test. Could show
problem inside walls.


--
Pat Farrell
http://www.pfarrell.com/

chriscc
2009-01-10, 05:28
Thank you for all the replies - you were right, the problem was definitely in the socket connection. I dismantled it, applied the age-old technique of blowing on it, re-wired it, and it works great! Thanks again!
Chris