Wireless speeds poor, line dropping daily

[#1]

Hi,

We noticed that since our contract renewed our wireless has been extremely poor. When we first moved into our property we had numerous internet problems and had an engineer round 4 times. The last time he switched the socket on the wall and it was smooth sailing for about a year after that. 

Our wireless performance is so poor we tried another router with no improvements. Our line drops nearly every day, sometimes multiple times. I'm working from home and this is extremely frustrating. It started off dropping at a similar time around 12-2PM every day but now it's dropping at different times, randomly. 

All our devices have noticed a huge decrease in wireless strength. My PC has dropped to a speed of 0.7MB, the highest any device can get is 1.3MB. Our usual wireless speed is between 9-13MB. We've noticed this drop across mobiles, tablets, consoles and both PCs. We cannot use the wireless with a stable connection without an ethernet cable. I've tried resetting, turning off and using another router.

I'm tired of ringing, tried of having engineers and tired of having this constant issue. Today alone I've had an orange light three times and it lasts for 5-10 minutes. If anyone can help I would be very grateful. 

Thank you.

[#2]

Use SEARCH on forum; there are multiple posts on improving wifi capability.
Saying that, PN's Hub One has a bad reputation for wifi performance.
Any alternative would be better frankly!

[#3]

I’ve tried multiple methods to improve the speed. I’ve tried multiple channels, I bought an extender, I tried a TP Archer router. I’ve gone through forums trying tweaks. I never had these issues before but suddenly my speed is completely unstable wirelessly and so is my line.

Even the Archer was unstable and would drop out which makes me think it’s a line problem.