Nissan main dealer unable to diagnose a loud and annoying squeak!

[vixcrack]

My nissan x trail, 2015 model, has  done 100k miles and more recently, its developed a squeak, which is more audible, when driving at a speed under 15 miles. The sound happens after driving for say a distance of 5 miles and it's like a loud squeak, almost as though, when the wheel is going round, its catching onto something. My local Nissan initially advised changing the brakes, but the sound has remained and they just told me, they don't know where its coming from, even though I have taken them on a test drive and they heard the sound. I have attached the sound, in the hope that someone on here might have an idea of what this is. Nissan have advised they have checked the car and all is good, but they can't figure out where its coming from. I hope you can here the sound, if not let me know, so I can upload on YouTube. Thanks. 

My recording 4.m4a

[vixcrack]

Here is another recording. 

My recording 7 (edited).m4a

[vixcrack]

Youtube link 

 

[vixcrack]

So with all the issues, I've had with my Glyn Hopkin garage, I have decided to send through a complaint to Nissan. Anyone, done this before and is it worth it or a waste of time?. So in my situation, was told that the squeak I was having, was coming from non manufacturers brakes, and these needed to be replaced. Since then, the sound has not stopped, and now the manager of the branch, is not responding to my emails for support,even though he does acknowledge the squeak is still there. Where do I escalate this to please? Nissan or Glyn Hopkin? Anyone ever complained before and what was your experience please?