As I understand it any digital information is presented as 'Tones?' on a Carrier within a Bandwidth of other combinations of Carriers. You would be hard pushed to make much sense of it without specialist monitoring/decoding test equipment.
(I may be wrong as things have changed in the 25 years since I retired, but that's the basic idea)

Link to website which explains the bits in the ADSL Diagram above --

https://kitz.co.uk/adsl/equip.htm

Jules
Try emailing the Chief Exec if you are getting poor customer service - contacting CEOs normally work if you have a good case of poor service.

It used to be worthwhile sending a letter to the CEO marked “private and confidential”, but this isn't as effective as it used to be now that so many people use it. However, it may be worth contacting the CEO of Vodafone by email. Vodafone UK's chief executive Ahmed Essam can be contacted via ahmed.essam@vodafone.co

https://www.google.co.uk/search?q=vodafone...nt=gws-wiz FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 82k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

This is the easiest diagram to explain what is going on inside your ADSL Copper Cable.

It shows your landline (POTS), and your Broadband Uplink and Downlink. The Broadband frequencies may vary in faster modems as more speed normally means more bandwidth is needed.

Click image to enlarge

Well Im both surprised and delighted.

Bearing in mind yesterday was a bank holiday, a chap from Openreach came first thing this morning. He identified a fault in the wire where it leaves my property and is in close proximity to some tree branches.
The wire looked intact.
He called for a cherry picker and then ran a new cable from the telegraph pole to my house. All done by 1200.

I had loads of messages from the both Vodafone and Openreach, keeping me updated, once Vodafone had triggered the response.
Once Id got through the initial repetitious and tedious filtering at Vodafone support the process went very swiftly.

 Jules

Great result  2014 Freelander 2 TD4 Manual Dynamic
1956/7 88" Series One Land Rover
1956/7 88" Series One Land Rover - undergoing restoration

Pleased to hear outcome.

Once again it shows that if you can wade through the 'Help Desks?' and speak to real person who has the ability and authority to sort the fault, then problems melt away.

God help us if they are all going to put in a level of Artificial Intelligence as yet another filter to help/obstruct us all getting real service. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 82k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

I dont think a God will be much help, unfortunately  Jules