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I have 3 ZyXEL Homeplug AV powerline adapters as per the one in the review below.

I have two plugged in currently, one into my Be / Thompson wireless router, and one into my desktop pc (box1). every now and then the link indicator on the adapters (the mains link, not the ethernet link) goes nutty, and performance falls off a cliff (see below).

64 bytes from box1 ( icmp_seq=1064 ttl=64 time=996 ms
64 bytes from box1 ( icmp_seq=1065 ttl=64 time=549 ms
64 bytes from box1 ( icmp_seq=1066 ttl=64 time=6.15 ms
64 bytes from box1 ( icmp_seq=1067 ttl=64 time=1400 ms
64 bytes from box1 ( icmp_seq=1068 ttl=64 time=812 ms
64 bytes from box1 ( icmp_seq=1069 ttl=64 time=11.1 ms
64 bytes from box1 ( icmp_seq=1070 ttl=64 time=1185 ms
64 bytes from box1 ( icmp_seq=1071 ttl=64 time=501 ms
64 bytes from box1 ( icmp_seq=1072 ttl=64 time=1975 ms
64 bytes from box1 ( icmp_seq=1073 ttl=64 time=970 ms
--- box1 ping statistics ---
1074 packets transmitted, 394 received, +487 errors, 63% packet loss, time 1082497ms
rtt min/avg/max/mdev = 5.945/598.452/3526.454/639.768 ms, pipe 4

Any idea how to diagnose/fix?

I'm on Linux so installing the Windows software that came with them is not something I'm terribly keen to do.

If I unplug one of the adapters, and plug it back in again, it behaves... for a while.

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It's broken. Throw it out (paying attention to WEEE).

One of the power lights was off as well, I think that unit is actually just faulty. I replaced it with the third unit and haven't had a problem since.

Thanks for additional help. I presumed it was something solvable before.

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Seems like a lot of flaky units make it out the door of many mfgs. I had some netgear products (DS2 chipset) and one of them died. PLC units tend to run hot. Glad you figured it out. It is amazing to have high speed available anywhere there is an electrical outlet. – dbasnett Jul 8 '10 at 12:45

What version 401? What exactly are the lights doing? I can't find the "goes nutty" light. You have Power, HomePlug, and Ethernet.

I worked with a PLC startup company for several years, and funny thing we used ZyXel for functions not in our box.

The thing's they don't broadcast are:

1 - The FCC limits the power that can be used because of possible ham radio interference, even though the frequencies are masked out.
2 - If the outlets your devices are plugged into are not on the same phase, then the coupling actually occurs as a radio transmission inside of the circuit breaker panel.
3 - If your house is wired anything like this

outlet --- panel --- panel --- panel - outlet

the signal will even be weaker.

Don't get me wrong, I like PLC, but I was never impressed with Intellon, though I never worked on the AV products, so maybe they worked the bugs out.

The commercial product we produced was quite impressive. I could walk into a 150 room hotel (Comfort Inn, Holiday Inn Express, etc) in the morning and by 5 o'clock I could have all rooms up and running on the internet.

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thank for the answer. how do i find out what version 401? it says model PLA 401 underneath. I mean the light with the little house on it that indicates activity on the power line (HomePlug) side flashes rapidly. The power is single phase. I couldn't tell you if they are wired on the same circuit, though one is upstairs, one downstairs, so probably not. – Tim Abell Jun 15 '10 at 13:09
@Tim Abell - probably in the management software that came with the box. Most homes are provided 2 phase 240 volts. Every other breaker is on a different phase. – dbasnett Jun 15 '10 at 16:35
ok, I don't run the management software as I'm on linux and it's not worth the pain I imagine it would be! And i'm definitely on single phase (which i reckon is standard in the uk) as there are clearly only two wires going through our meter and into the "consumer unit" or fuse box as I like to call it. (single core 50 amp type things) – Tim Abell Jul 8 '10 at 6:44

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