Really bad crackling on line cant hear any conversations phone rings ok and dials ok but cant hear anything but crackling

As Andrew Taylor stated, you could have service problem inside, or outside line trouble, is it worse when raining or wet out and better on warm dry days, sure sign of line problems.
You may also have a faulty phone which will act identical to this, as phones get older and dropped often enough, the circuits start to wear,burn,come loose and cause this static or interference.
Unplug all your phones and try a friends known good phone to see if static goes away, if it does, plug your phones back in one at a time, until you find the bad phone or bad phone jack..
press the helpful button

CenturyLink How to troubleshoot for static or noise on your phone line or...

http://support.sasktel.com/app/answers/detail/a_id/15097/~/static-or-crackling-noise-on-your-phone-line

https://iihelp.iinet.net.au/Troubleshooting_Home_Phone_for_Line_Noise

if only happens on certain calls it could either be the handset itself, a week point on all corded phones is the cable between the handset and the body of the phone. whilst talking to someone on a call wiggle the cord where it enters the handset, does it crackle if not do the same where the cord enters the phone body, if no crackle likely not phone.

next select a line if you have more than 1 line note which 1 and dial 17070. this will BT autotest the line. if more than 1 line on system do same for all lines. check with your system admin if there are quick codes to select individual lines, eg dial 9 for any line or 81 for line 1 82 for line 2 etc .

if you get crackle still on 1 of the lines get your maintainer to check the lione at the cable head where lines enter building

Change the channel or code setting. It's also possible the 'pairs" for your house and your neighbors are "crossed". Does it happen with all phones or just the cordless one. If it's all phones, the problem is in the phone lines.

Yeah is the volume is all the way up and you still cant hear anything the only options left are to plug in another phone that you know works to make sure its not the phone line or socket at fault and then take the phone back for a replacement.

No dial tone on telephone set? could mean alot of things. Phone went bad, jack is bad(test in different jack or from a network interface, either inside or outside. depending what your dwelling is)
Just to point out a fact, when dial from your mobile to that number that has no dialtone, that ringing sound you hear is from the central office that is putting out that ringing, it has nothing to do with the phone you're trying to ring to. You would hear the ringing sound, even if all your phones were unplugged from every jack in your dwelling.

i have a GE 6.0 cordless telephone, i know tha it's ringing the number comes up on my television but I can't hear it ring?

Check the phone cable you are using for your POTS line. Attach a phone directly to the phone jack and see if it is clear or static without the device.