A question from the sweet old days, I live in Syria and I am having a strange problem with my DSL phone line, I need some help please

Hi, I have a 4Mbps ADSL2+ line in my home (which is a big deal depending on where I live), a 300Mbps D-link Router and a 60 Meters (65 yards) cable from the phone cabin to where the router is, so up until 2 weeks ago, everything was OK, Attenuation Down Stream was 30 and up stream was 25, SNR margin for downstream was 17 when the electric power was off and 10 when it was on (we are used to getting more noise when power is on, it's everywhere), but recently, the line is kinda having some issues, The router connects as usual, and then after a couple of hours, SNR margin starts to drop till it gets to 6 or 5 and then it disconnects, and when it reconnects it gives me 3Mbps (which is still OK), but it keeps disconnecting and giving me slower speeds until it becomes somewhat stable somewhere around 1.5Mbps (sometimes less than 1Mbps), with SNR margin of 6 for both up and down.

when I pick up the phone (which is connected through a filter) I hear so much noise when the speed is at it's worse, and I get Attenuation Down Stream around 40 and upstream around 32 then.

keep in mind that I have an aluminum wire that connects the cabin to the router, and it is now a year old, and we kinda have a rainy weather in these days, but the noise isn't related to the rain or the wind, sometimes I get a noisy line without rain or wind.

here is what I have tried so far:

1- examined the wire where I can examine it, and removed some of it's damage that has happened because of the friction against some walls over the past year.

2- connected the line to the router directly without any filters or phones.

3- tried different routers.

if the problem is from the wire, then why does it give me good speeds sometimes all of a sudden?

and since I can replace the wire with a proper copper one (but it does cost me some money), should I consider that? or should I try something else?

any help is appreciated, this thing has been driving me crazy, By the way I am a medical doctor so I don't really know if any of the above makes sense :D, but here is why I am here asking you guys what I should do.

and sorry for my English, it is my second language.

Thanks