Noisy crackling on phone line

[#1]

I'm getting a crackling noise when using the phone.  I have gone through the phone troubleshooting guide and attached a corded phone into the master socket, but the annoying crackling is still there.
Also the speed on my fibre broadband has dropped massively and keeps cutting out.  It has gone from 74Mb download to 10Mb.  I am guessing the wet weather has affected the phone cable going from the green cabinet into my house.
This happened last year and the BT engineer couldn't find the fault.  I raised a new ticket and had an appointment with a BT engineer yesterday but they did not turn up and didn't bother to contact me to warn me of this.  Has anyone had any similar problems with noise on their phone line? 
 

[#2]

Generally any noise on the line will mean something a bit dodgy with the wiring between your master socket and exchange - this will play havoc with the broadband signal as well
To rule out internal extension wiring, have you tried popping the front off the master socket and connecting directly to the test socket (assuming you have a normal NTE5 type socket) ?

[#3]

You are due compensation for the engineer not turning up: http://www.openreach.co.uk/orpg/home/updates/briefings/generalbriefings/generalbriefingsarticles/gen...
@DomS - he's on fibre and therefore will have a filtered faceplate.
@GavH82 Does the modem plug in to the master socket or do you have a data extension? It's worth doing as DomS suggested and checking the phone when plugged in to the test socket to see if it is still noisy - you'll need to remove both the small faceplate and the filtered faceplate with the VDSL socket to access it. Do you know the handset you used is good (perhaps test it on a neighbours line)?

[#4]

Yes my modem plugs straight into the master socket and I have no data extension cable fitted.  I have removed both the front faceplate and the filter and connected the phone to the test socket.  The crackling noise is still there.  The phone is brand new so I have ruled that out. 
I suspect as Dom S has stated that there is a fault in the phone line between the property and the street green cabinet (around 150m away).  I just need an engineer to turn up and confirm it now.  Cheers for the replies.

[#5]

Hi there,
I've asked one of our agents to chase our suppliers about this, in spite of what was booked when the fault was raised it's showing the appointment as being booked for the afternoon of the 24th. We're just chasing them now to find out why that is and whether it can be brought forward or not.
Really sorry about this, when would be best for us to try and rebook it for?
EDIT: Thanks for your time on the phone, that's being rebooked for you for the 18th Jan (this Saturday) in the afternoon, hope it gets things sorted. The ticket will be updated shortly to confirm.

[#6]

Thanks for chasing this up Matt.

[#7]

Fingers crossed everything goes well - let us know what happens !

[#8]

For anyone reading this with a similar problem the fault has been fixed.
The junction box just outside the front of the house (small black plastic box above the front door) was full of water and the phone line inside it had corroded away.  The engineer found and fixed the fault within half an hour. 
No more crackling noise when using the phone.    Internet connection is better as well, just have to wait a couple of days for the speeds I was getting before.

[#9]

Excellent news - thanks for posting back some positive feedback