TP-link powerline has developed slow speeds.

[#1]

Had a powerline since last July.  Been working fine until last week or so.  Now connection speeds have dropped from mid 20s to between 1.5 and 4.  This is only over powerline.  Wifi in line of sight still gives high 20s to 30+.  one month ago moved to Plusnet from Sky.  No problems for first 3 weeks.  Now powerline pretty well useless.  Yesterday had live chat with TP-link techie.  Basically spent an hour cloning powerline to wifi.  Was satisfactory (16Mb/s) for an hour or so, then started dropping.  This a.m. is back down to 1.5 again.

Certain that problem is with the powerline not Plusnet router, but if anyone has helpful suggestions I'm all ears (or eyes).

[#2]

@carolesped  powerline can be exremely flaky. The data can be corrupted by electrical noise on your mains wiring caused by faulty filters on electrical appliances. This might be in your or near neighbours home.

Do you have any appliances running at the same time, washing machines, vacuum cleaners electronic toys etc.? If so try switching them off and see if things improve.

Personally I have had nothing but trouble with using powerline so threw them out and installed Ethernet cable around the house. If you need wireless at a remote part of the house I have found that if you plug the wireless end of the powerline pair into the Ethernet cable it works as a reliable Access Point, you do not then need the other unit.

[#3]

Baldrick1,  thank you for your cunning plan.  Ethernet alone would not be enough.  I need that for a Youview box, but also wifi extension for tablets/phones.  The powerline gave me both.  Running cable will be a nightmare.  All internal will make the Hampton Court maze look straightforward, going outside will involve the attic, drilling twice through external walls and then adding a wifi extender somewhere.  Hard decisions.

[#4]

Also it looks as if the powerline unit is the problem.   Unplug it and it works ok when replaced.  For a few hours.  By the following day the speeds dropped right off again.  Wonder if something inside is overheating?

[#5]

@carolesped 

It sounds like a rhermal problem. It might not be overheating but being caused by an internal component failing. It's not unusual for electronic components to fail in a mode where even the natural and normal internal temperature rise causes excessive component 'leakage' which might affect performance before failing completely.

[#6]

Baldrick1

Thanks for your input.  Seems entirely probable to me.  Now the fun starts.  8 months old and failing.   TP-link wants nothing to do with the problem because the people I purchased from (Currys/PC World) are 'not authorised resellers of TP-link'. More slippery than a bucket full of eels in silicone!  Have to wait to see how C/PCW  respond.