Hi @airlam65 and welcome.
I'm sorry you're having so many problems with the connection. Is there any noise on the line, especially during the drops? Can you check that by connecting the phone to the test socket behind the master face plate and dial 17070 option 2. Let me know how it goes.
If there is any noise on the line you will need to report a telephone fault. At this stage don't mention the broadband problem. Once the noise has been cured your broadband connection will also improve.
Yes, the line should be silent unless you are using a cordless phone when you may get a slight hum. It's always best to check with a corded phone.
On another note, a cordless phone won't work in the event of a powercut whereas a corded phone will.
I had Infinity 2 terrible in the winter. I noticed that it changed as the weather did i.e. freezing melted. A long dialogue with people who sounded like that they had never experienced freezing resulted in testing the line for silence. It was rowdy. One more call to the never frozen assistance resulted in the threatened it will cost you line. Look it is not a quiet line.
Engineers came on two days and after climbing here and there resulted in a silent line and almost max up/download speeds with Infinity 2.
Do the line test and tell them your result. Because I seldom use the land line phone and only to answer calls I had not noticed the row going on.
You should still report the telephone fault which was there when you last checked.