Adsl phone line problem

Hey all, I really need to get an opinion from guys who know technical things about the phone lines and adsl.
Whell my problem is this :
Since a few weeks, my phone line which is the only one in my house and has adsl connection with the adsl splitters installed, has been dropping completely dead for a few hours and then back on again.
I called my provider, they checked the line outside the house and they said its crystal clear, no problem on our side. Unfortunately for me, they came at a time that the phone line was working just fine and they didn't find anything...
So after a couple days, the line was dead again for a whole day. The next day I discovered that if I called my home number from a mobile or any other number, the line would come back to live and work just fine, until the next "death".
In this week though, things changed. My phone line now has loud noise, with squeaky sounds and my modem cant get a synchronization. I tried to change the phones, remove all devices, etc but nothing helps. The line just keeps having loud noise, my adsl modem cannot connect, until the line is fine again by itself.
What do you suggest? Maybe hiring a person to check my home lines? Ty a lot.

With your ADSL kit disconnected do you hear noise on your line with just one corded phone plugged in? e.g. try the quiet line test (dial 17070 option 2). If so ring BT and report a voice fault. Don't mention ADSL. Fixing the voice fault will also fix the ADSL problem.

when you say noise is it a crackle?

sounds like an high resistance dis, are you fed overhead or underground?